Agreed, making sure the engine fits and the vitals like the alt and waterpump function is top priority, I'm just bouncing a handfull of ideas off of everyone to get a different perspective
If I do indeed need to move it back to fit it all properly, I'll notch the seat a bit more and redo the cover, no big whoop there.

I'll have the same issue of where to put the oil cooler and A/C condenser no matter if I move the trans back or not, but if I move it back I can cut the upper rad support and shoehorn the rad in at the same ungodly angle and arangement I had it in before.

I won't be certain as to how much or how little room I have till the engine's in there without it's pan for a test fit.

Looking back, it fit fine in the other truck with the original pan after some frame notching, with 1/4" or so between the pan and swaybar. The pickup is ~ 2 inches long and rests on the pan bottom for all intents, so I have ample clearance there after I remake the pickup flange and put the relief on a 90. I measured out from rear of the block to oil pump, and I seem to have enough room to clear the front frame member as well, but I'm not entirely sure.

If I can catch a few hours shuteye I'll hopefully have some definitive measurements by the end of the day.