The 6R80 has a maximum torque input of 590 lb ft. so it would handle the torque. Main issue might be finding a torque converter compatible with a 4bt. Destroked probably already had an adapter plate that should work and may have a flex plate as well. Their adapters use the Ford 6.0 diesel starter. You'd need to check with them on that. That transmission comes mated to small diesels in the Ranger truck line but doubt those have torque peaks the same as Cummins 4bt.