we put a jeep long input shaft t-18/dana 20 combo beind a amc401 in my buddys 87 wrangler and he had pleny of rear drive shaft between the dana20 and the dana 60. it was considerably longer than mine when i was still running the stock wheelbase on my jeep.

brian wilson
80 cj5 "high 5"
stretched to 100" wb
351w/np435/d300/d44/d60/detroits/4.56/35ss/bdlocks