poke around on realoem and you can occasionally answer your own parts questions - http://www.realoem.com/bmw/showparts.do?model=1113&mospid=47309&btnr=23_0380&hg=23&fg=10 A lot of various BMW model motor mounts are probably relatively similar; for instance some six-series motor mounts work fine for E30's; you have to cut off one nub, and it's a smidge taller, but its a harder durometer rubber than the stock E30 mount. You need answers from someone who's had the various motor mounts in hand for comparison. Zionsville autosport probably has the most comprehensive info and stuff for a conversion. Either buy this (E30 Conversion manual on CD) and get answers to all your questions (ya, I know, it costs waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaay too much, why don't they give it away free, you couldn't possibly afford it, it's not worth the money, yadda-yadda-yadda-yadda-yadda) or ask around and find someone who's already bought it and would be willing to answer your questions so you can continue to source whatever parts you need as you progress through the project. Unless you find someone who can give you the answers you need and know it won't be wrong, I suggest buying parts from someplace that will let you return and exchange them just in case you do end up with motor mounts or transmission mounts or crossmembers or whatever that won't fit or work. All the info might well be out there on the 'net, but you may just have to slog through 60-page threads to get it if that's your only alternative. Glad you're making progress, keep chipping away at it and you'll get there.