Thats what I thought.Thinking of a 2.0 Turbo petrol, front loom and ecu from donor car. Will try to post vids of the work being completed. Thanks for advice.Both the Mk1 and the Mk2 Lags had the F4R as an option.
So mechanically should be sound.
The Mk1 would need to be a petrol burner unless you want to be replacing the whole fuel system as well.
Depending on which engine is in, gearbox/dif/final drive ratios may be different so need to swap as well.
Then your problems start.
ECU and possibly a good chunk of loom from donor car.
If a donor ECU, UCH and keys also needed...or a bypass of imobiliser.
IIRC, you were thinking of a trackday beast....so may want to look at adding a turbo.
Will involve a remap and possibly further input via CLIP or other suitable diagnostics.