Nick is very active behind the scenes developing parts and offering support for shops, and between that and his full time engineering job I can't imagine he's got a whole lot of time to burn on the forums. I've tried to pay it forward and alleviate some of his load by helping a lot of you guys out to the best of my abilities in offering advice and suggestions since he's been a massive help to me with these conversions.
To answer your question, Adam, the conversion parts that I use are almost exclusively those of Nicks -- primarily the LT230 to 6L80 adapter, engine mounts, shifter pedestal (for Lokar equipped trucks) and radiator. Depending on what the build calls for I may stray off into my own realm here or there, but Nick offers such rock solid components that it's hard to justify.
I'm on swaps 4 and 5 currently so most of the bugs are ironed out on my end at this point. I'm more than happy to offer guidance to anyone finding themselves lost.
-Ash