Oldblu49,
and Keahi,
You are the first to provide info on an older rear end that has a gear reatio and the 6 lug patern.
I have looked at all the pictures I have seen on the internet of AD trucks and it seems the hot rod trucks are almost all 5 bolt and the restored trucks are 6 bolt lugs.
My initial thought is to stick to 6 bolt. I don't know enough yet or have not researched on the available 5 or 6 bolt after market wheels.
I also don't know how hard it would be to find a Task Force series rear end for reasonable $.
Oldblu49, is the Task Force rear end the same width as the AD trucks?