Well the 5.0 is now in the Fairmont, so far the compatability of the conversion has really surprised me.
Firstly much to my surprise, and contrary to what most people told me, the engine crossmember did not have to be changed. The mounts slipped on with ease.
Also the wiring looms for the dash and engine are also almostly entirely identical, with only two additional plugs on the XR8 loom.
I will however have to drop the up spec power steering from the Fairmont though as the XR8 loom does not faciliate it. It's also looking likely that I will also loose Climate control with the changeover.
I did changeover to the XR8 upper control arms when i changed the diff as well, they had a slightly different angle to the standard which from what i've read offers better traction off the line.
I'm hoping to have the whole conversion completed by Sunday night, just engine ancillaries, gearbox, tailshaft and dash to go. With the exhaust due for fitting wednesday next week everything is coming together well.
Hopefully I'll have pics of the motor when the job is all down.