Think the xr3i bottom will need bits doing to it for turbo to work i.e oil return ect

id use RST head and block and gearbox, fit efi maifold manifold with adapter plate, engine loom should plug striaght into car loom as long as is the the same (ofab ect) if its a late RST block? you got a hole ready for the cps (but u will need a fezzy flywheel for the teeth) or forget that and find a sierra 1.8 crank pulley, lower timing cover with cps on it (needs trimming) doing this u will need a sierra 1.8 alternator pulley and match up a belt. or forget that still and speak to Mr Jano Oddkid who sells trigger wheels and sensor for the cps bit

Think thats it matey