Coyote and TDK frame
I am using a TDK frame, 3rd Gen Coyote and BC Broncos engine mounts. Got a 10R80 behind it with an Advance Adapters kit to the Dana 20. No body lift, so I had to make some room in the trans tunnel. Also had to move the firewall back to clear the vacuum actuators on the intake manifold. Moved the master cylinder 1-1/2" to the left and the heater 6" to the right.
The biggest problem is that the 10R80 is so much longer than the old C4. That puts the front driveline yoke so far back that it would not reach the pinion on the Dana 44 without lifting it to the moon. I had Western Differential (Tucson AZ) make a 9" front axle with a 10" pinion offset (the Dana 44 is 5" offset). Even then, I had to go to a Moroso road race pan and modified it for clearance to the diff. Also C-sectioned the left frame rail for up travel clearance of the axle.
Look at most of the Coyote Broncos and you can see daylight over the tops of the diff housings. Leno has one; check out the episode on Leno's Garage about that (YouTube). It goes like hell in a straight line but forget about cornering.
I have been on trails where I was worried about tipping over. I'm not building a rock crawler, but this Bronco will have plenty of daylight under it and will still have a reasonable CG.