I put a set of of four, eight lug dually adapters on my 53 one ton. They are supposedly off a 78 3/4 ton flatbed dually bought new from a dealer according to the man I bought them from. Having never seen a 70s 3/4 ton dually, I cannot verify this other than I pulled them off the truck and they looked like they had been on there for 25 years. It was a farm truck and I think the dealer must have had some sort of conversion done to it, maybe it came as a cab and chassis.
I have occasionally seen this same set available on ebay.
While I cannot recommend them due to the slow service, Stockton Wheel makes a new copy of the steel adapters I have. He has them on his truck.
Steve, what I have would work perfect for your situation. Like I said, available new from Stockton if you want to wait on them.
