Starter motor loom??
You basically are using the RB20DET engine loom (start motor would be off that i assume), the RB20DET ECU, and from that you splice into the dash loom to get your little gizmos working. But most of that stuff is separate to all the engine sensors and that sort of thing.
All your coil firing and ignition stuff will be controlled from the RB20DET ECU, so don't stress about that side of things.
Some adaptions need to be made also, i believe for the fuel pump system, and other bits and pieces such as the guages, speedo, tacho, etc.
Anyhow, I will admit I am just going from what I have read, not done. Bozz knows all.. In fact just bolt it in and pay him $500 or whatever he charges to wire it up for you
Apparently not massive difference between stopping power of R31 and R32 brakes, so not required to be changed for engineering in many states.
LSD would be nice.. you're going to have troubles with the single spinner and feeding power through it to the ground on takeoff. A diff specialist told me the borg warner *should* be strong enough in terms of holding out (e.g. not go cactus), but LSD would be better. The single spinner should handle the power and stay alive for a while, if you don't do massive burnouts, take it a bit easier right off the line, and crap like that.
and before you ask.. no you can't fit an LSD from any import model skyline in. You'll have to get an aussie B/W LSD that fits the housing.. can be hard to find these days. Expect to pay around $1k to go to an LSD.