very easy as far as conversions go.
I put a ca18det into a s3 bluebird a few years ago and that bolted up to standard engine mounts and standard gear box
and we put 1 into a mates pinny wagon.
all it is
step 1 unbolting the ca 20
step 2 bolting in the ca18
step 3 wiring (very easy 1 of the plugs had all the wires u needed from memory)
step 4 plumbing every thing up (exhaust, heaters ,intercooler, thermo, fuel)
step 5 wish u had of put it in a bluebird instead of a heavy pintara.