Just looking for a bit of advice.

I have a 2005 face-lift and my upper tailgate has started with the usual bubbling and the bottom edge has pretty much had it.
I've seen a 2012 one for sale and was wondering if it will fit?

That's a tricky one to answer, there are 3 different part numbers for the tailgate BHA760010, BHA760020, and BHA760090...

BHA760010 is listed as 2003-2009

BHA760020 there is no info, but appears to have been superseded by the earlier part number

And BHA760090 is shown as 2009-2012

Now there is a difference to the amount of sound deadening in the tailgates, and believe it or not the earlier ones are better made than the later.. you can hear the difference!

And I think I've found the difference... the lock assembly is a different part number from 2009 to 2012, so there has been a change.. so based on that I would think it unlikely that it would be a straight swap. Personally I'd be looking for an earlier tailgate.. it would appear that the earlier the car the longer the bodywork lasts.. 2002-2004 BMW build being the better  Yesterday I couldn't spell Engineer... Today I are one!
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Former long term L322 owner, Up/Down graded to a Classic Tractor!