Finally managed to source a set of steps. Came with 2007 wiring loom.
I already have 10-12 ECU. (I haven’t checked if plugs are same yet)
Anyone know the difference between 07 and 10-12 wiring looms?

Not completely sure -- the 2010-2012 fitting instructions PDF is in the wiki under the 'Body' section. Current: 2011 FFRR Vogue SE 4.4 TDV8
Previous: -
2004 FFRR Vogue 4.4 V8 with LPG
1997 P38 4.0 SE with LPG
1997 P38 4.6 Vogue with LPG

The instructions that have information for both models only shows a few extra wires at the button.
But the instructions that are solely for 10-12 show a few more connections at the Fusebox too.

Having only fitted a set to a 2011, I suspect you'll struggle without the correct wiring harness. Current: 2011 FFRR Vogue SE 4.4 TDV8
Previous: -
2004 FFRR Vogue 4.4 V8 with LPG
1997 P38 4.0 SE with LPG
1997 P38 4.6 Vogue with LPG

It seems the diagrams are different. However using the 07 loom and 10-12 ecu I have got it to work.
Just connected as per the dual instructions. I don't know what the extra connections at the top are for. I don't have the switch as yet anyway.
But works normal otherwise.

The switch is important -- enables you to enable and disable steps -- locked in, or out. Current: 2011 FFRR Vogue SE 4.4 TDV8
Previous: -
2004 FFRR Vogue 4.4 V8 with LPG
1997 P38 4.0 SE with LPG
1997 P38 4.6 Vogue with LPG

Turns out there was a switch in the bundle of parts. I had ordered one.
All fitted and working as expected.

I bought the loom and ECU in anticipation of getting the steps from John Craddock. After three months waiting they said they couldn’t get them anymore.

So I’m still looking for steps if anyone knows to a set. 2010 MY Vogue SE TDV8 3.6 Stornoway Grey- fully loaded

During my search I found another set for sale. They wanted £350. I can get contact details if interested.