well i wouldnt spend any money if i went the 850 route, i've got a nice 850 here that just needs a 2nd gear synchro, and the one thats in the car is unknown.. once im done with my 1360 i'll whip out the "start ya bastard" and see if i can get her to crank over.
if i do run an 850 i will cannibalise a 12g202 and probably some old cooper headers and a single hs4, that should go arrite.
or i run my screamer 69ci stroker smallblock

i'll wait and see if anyone else runs an 850 i reckon