15x6 on 5 lug conversion

[bpope]

Well, I made the voyage down to TX over the weekend to pick up my '65 Step side and drove it back the 7 hours back home. Needless to say, I have bonded with this truck. I am wanting to put the 15" x 6" steelies from the '72 (I believe) and up trucks. It has the 5 lug conversion, but I'm not really sure how it was done as I know only about the '88 on up trucks. I have attached pics of the setup, now and I'm wondering if anyone has any insight on whether the narrower 5 lug wheels will fit. It currently has 15x8 truck rallies on it. Sorry pics are sideways, let me know if I need to rotate to help. Thanks!