sr20det brakes arnt that awesome. id suggest going some sort of multi piston brake r32/33 or s14/15. its all bolt in, im not 100% sure what you do if you want to keep it 4 stud, what hubs and shit to use but providing you get the right combo of parts it bolts in, nissan seems better then toyota for interchangeability.
ca18de, i guess you want to check if it came with a r180 or r200 diff. if its r180, then r200 diff and half shafts should slap in its place and you shouldnt break a r200 diff too easy.
what wheels are going on this? surely not wats?