i'm on the way to finishing up my VG30E swap in my FC. all i can say is granny's kit took alot of work to get things fitting up right.
i had alot of missing parts as well, and the measurements they took for the engine mounting do not seem to be very accurate... it's been about 5 months total for this swap so far, but it could have happened a lot faster if i wasn't waiting on granny's to send me a part that they forgot, or was incorrect. be prepared to make lots of little modifications to their mounting kit to get everything to fit up right. though, once i get the wiring and all the little fixes for the car done, it will all be worth it to me. on a side note - to simplify the swap process, i removed everything from the VG30 and the FC engine bay that were not required to run the engine (no powersteering, AC, heat, emissions, etc.).
budget was the main reason for this swap, so i've been trying to do things as cheap as possible. i had a 300zx donor car and all the parts were in good condition. i bought my FC for 450 bucks with a blown motor, granny's kit for 700, 100 dollar walbro, lots of miscellanious autozone things, plus paying a friend of mine 500 bucks for a complete wiring job (couldn't finish it without him), etc. etc.... i'd say i've spent a total of maybe $2,000 dollars or so. i still have to get a custom exhaust made after i get everything mounted in it's final places and get the car ready to drive, and that should be another 500... so $2500 i guess.
i suppose i could have just bought another car with how much i've spent.... but the way i see it, it would still have been a used car that i knew nothing about. this way i have an engine and tranny that i know are in good shape (i was driving the Z before it got used for parts), and i've done alot of work with the whole car so i know it in and out. it will also sound alot better than a rotary, it's cheaper, more reliable, more torque, and better availability. turbocharging is also done easily since the 300zx is a native turbo car, so power isn't much of an issue either
but anyway, i'm kind of new to working on cars so the whole thing is a great learning experience. building this car is like a dream come true =p