From the front for me. The main reason I reinstalled as an assembly was the pilot bearing and input shaft fit for the trans snout is really tight! I had the trans out once by itself and fought it for several hours trying to get the darn thing back in. Light press fit I reckon...
Good point about bell housing alignment as well. Fortunatly the ERA's are so much easier to work on (trans tunnel comes out) than many other replicas. FFR with a T5 comes to mind, you aint got enough beer to get ME to help that trans!