Dont think it was savagely bad actually. At the end of the day the carlton is RWD, so as long as you can get the chosen GBox and Engine physically mounted, you get the prop made to fit, wiring shouldnt be too bad as long as you keep the ECU loom in one piece. Think he did have an issue with gearstick location however!
I speak theoretically of course! But as a general rule, RWD cross-marque engine swaps are much easier than FWD ones
'twas me....i did a thread a while back regarding the fitting...was quite easy but the gear stick was a pain as it hit the dash in 1st/3rd..
had 214 bhp and 311 ftlb @wheels with a "small"T3 turbo"
but it went bang at 150 with no oil in it?

it needs 1 big end shell

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