There aren't that many turbo e34 M50s around. I couldnt find one when i turboed mine, but if you look around for e36 turbo stuff you will find plenty. Most parts fit directly, and the rest need slight modification, but they all work.

www.bimmerforums.com
goto there FI section, but watch for who you believe, alot of people BS on that forum.

www.activeautowerke.com
they have good kits but they are expensive as hell

http://www.cardomain.com/ride/789296/1
some pics of my old turbo e34