70 Axles issues...... confused

[jetfixr]

I decide to start working on the old truck again. One thing I always hated was that it was tough to find nice rims for a 6 lug. So I thought about doing a 5 lug conversion. Just my luck, I guess they changed the width of the rear-end mid-year in 1970. So I am not even sure what rear-end I have. I know it is a posi-traction read-end, which I would like to stick with. I have heard folks say that later model axles would slide right in, easy fix. Without knowing exactly what I have or exactly what type of donor vehicle I need to be looking for it is kinda tough. Does anyone know how might be able to ID the read-end and what might be the possible donors? I know Early Classic can hook me up with the conversion axles and new rear drums but I am looking at a bill of about $500 if I go that route. I would much rather put that money toward the rims. Thanks