Ok, here in Estonia, Finland and Sweden they check it just from under-side. So obviously DPF-deletes are done so that it is cut open from upper-side so it won't show when reinstalled. Didn't know that you guys got so thorough inspection there, that they check it with some cameras or endoscopes etc. what a bummer.

Check with mirrors or tapping the outside of the DPF, easy to tell if it's been tampered with. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

As Kokamagi explained, we're a bit more fortunate with MoT (EU-regulations) inspections in Scandinavia (and Estonia it seems).
The inspectors can't be arsed to spend time chasing down people who go to the trouble of gutting their DPFs.

On another note, Kokamagi is correct:
The EGR system's function is to lower NOx-gas generation by lowering the combustion temperature (otherwise the combustion makes the otherwise inert gas Nitrogen to react with Oxygen) A nasty side-effect of this is carbon and soot build-up, caused by exhaust gases being re-introduced to the combustion, and the resulting lower temperature.
A modern diesel engine, and especially a remapped one will in most cases run so clean and hot that there's no need for a DPF.

Conclusion: Ditch the EGR I you can get away with it. And while you're at it ditch the DPF as well. It will have absolutely no detrimental effect on the life and health of the engine, on the contrary.!

Faukstad, my point exactly.

What are the real practical problems on a TDV8 4.4 ( not 3.6) that DPF and EGR removal is solving? Many reports of engine or component failure or loss of performance or economy? OK it sounds nice to have a clean intake but it's also nice not to be throwing particulates and NOX into the air that other have to breathe. 2012 TDV8 Vogue (L322)

A healthier engine..

DPF and EGR systems are there because of Euro-3/4/5/6 regulations. In other words, politics.
I don't think this is the right forum for discussing politics and global warming bla bla, but in general; any, and all engines run healthier (less particles, less soot, only combustion byproduct being CO2 and water) without all of these regulatory add-on systems. NOx-gases aren't really a problem for the environment as such, but more for localized air quality, but to minor extent.
Remember: The EGR is there for regulatory (emissions) purposes, and the DPF is there because of the EGR system.

In the early years of the Euro-regulation implementations, and when EGR was first introduced, it caused so many problems and gremlins in cars that even dealerships installed blanking kits and delete systems to take it out of the equation. At least here in Norway.

For practical reasons removing EGR and DPF systems isn't widespread and common practice enough to have any measurable effect on air quality. And as a bonus: the car will produce more power, get better fuel economy, AND as a result produce less CO2.

In what way's is the engine 'healthier' ?- what specific problems are found on the 4.4 with regards to intake soot that restrict performance, shorten engine life, reduce economy, cause component failure etc? These engines have been around for well over 10 years now and are still used in the current SDV8 in the L405 and I'm not aware of any major issues myself.
BTW clean air (esp in cities) is not a political issue.
Also I dispute ( again) that cars are fitted with DPF's due to an EGR being there. 2012 TDV8 Vogue (L322)

The "problems" with running EGR and DPFs aren't specific to the 4.4.
Hence my statement that any and all engines will benefit from EGR removal.

Engines sooting up, carbon build-up, EGR-valves failing, valves getting stuck, DPFs getting clogged up (usually because the EGR isn't functioning which leads to DPF regeneration not taking place), poor gas mileage (by poor I mean compared to a car which has the EGR removed). The list goes on...

An engine which can breathe freely, and digest what it's meant to digest (Air and fuel) will run cleaner (the definition of clean is debatable, I agree). Soot/carbon is a result of an incomplete chemical reaction/combustion.
HC(diesel in our case) + air = H20 + CO2 + NOx

I'm not saying you should run out and get it all removed, I'm just saying there is reason and just motivation behind removing it. What you do with your own L322 is entirely up to you.
And you can dispute to your hearts content, DPFs and EGRs are emissions systems put in place to comply with regulations (politics).

This thread is specifically about the TDV8 4.4 and not other engines such as the 3.6 which have 'legendary' EGR valve issues.
Your list of reasons for removing the EGR and DPF on the 4.4 are a 'solution' in search of a non existent problem.
Pollution effects everyone - whoever you vote for or whatever you choose to believe in. 2012 TDV8 Vogue (L322)

It seems you have misunderstood.
The OP is not interested in your opinions on pollution or what you deem non-existant problems related to EGR removal. He obviously has a desire to go ahead with it, and has his motives for doing so.
I'm an engineer, and I have 30 years of automotive experience. And I completely agree with him. In my opinion EGR and DPF is the work of the green devil (please, meant sarcastically) and I support his venture.
And finally: No, removing EGR and DPF will not harm his, mine or your engine. If done properly.

As an automotive engineer you wil be more qualified than anyone to advise the OP on how to go about this - any suggestions to share beyond it should be ‘done properly’
You have in your capacity as an automotive engineer clearly stated that no harm can come to anyones engine which is very reassuring. Could you also therefore state what power, economy and service life gains could be obtained by this procedure and also what extra emissions in terms of particulates and NOX will be generated so others can make a properly informed decision. Often advice on this and other forums is based on nothing more than opinion and anecdote so input from an engineer with 30 years of automotive experience is going to be on another level. With some hard facts on hand I may even be tempted to do it myself! 2012 TDV8 Vogue (L322)

To backup Faukstad I am also an Engineer (not specifically engines) and automotive mechanic of fairly considerable experience (3 decades). The question you posed him is impossible to answer, such as 'How long is a piece of string?'.

I shall attempt a visualisation for you to imagine and return the question to you; take two engines that have very similar working lives but with one notable difference - one has an additional pulley driven by its serpentine belt that drives an extra pump that puts a constant additional load on this engine. Both engines are run exactly the same and have exactly the same maintenance (although the engine with the extra pulley requires more frequent fuel fill-ups). Fast forward to 5000hrs of use later and the engines are replaced by new and offered for sale.

Which will attract a higher value and why, given both have had the same working life..? This is not an attempt at patronising anyone, but simply a way for a non-engineer to view a common interpretation within a simple engineering scenario.  Cam

2011 TDV8 Vogue in Stornoway Grey

After 5000hrs of life or x miles or whatever - if both engines are still performing within spec why would you pay more for one than than other? 2012 TDV8 Vogue (L322)

You would pay more for the one that had done less work surely? The additional work that one has done would lead to additional wear on the bores, pistons, main and big end bearings as well as potentially turbo, fuel pumps and injectors. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Why pay more for something that will do the same job? From an engineering perspective and engine with less wear will obviously last longer but what use is an engine that lasts say 300k miles over one that lasts 200k miles to the average buyer? Talking specifically about the TDV8 4.4 we are seeing mileages well beyond 200k miles (with egr and DPF) by which time the value of the car is dictated by other factors. Low mileage cars are not more expensive soley due to engine life. Engines are probably the longest lived mechanical part of any car these days often outlasting the other parts. 2012 TDV8 Vogue (L322)