Trying to clear up 15x8 truck rally confusion

[Luke87gt]

Hi guys,

I’m planning on picking up a set of OEM 15x8 6-lug (4.0” BS) truck rally wheels tomorrow. I don’t know which Chevrolet model they originated from but I understand that they made these wheels from 67-87 C10/Blazer. Somewhere in that time the stud size changed from 7/16-20 to 1/2-20. Additionally some of these rallys came from 4wd and some 2wd c10/blazer.

I assume these are all interchangeable and will fit a ‘69 c10 2WD regardless of what c10/blazer they originated from? Would you please help confirm.

I’m trying to avoid buying wheels that won’t fit my truck (wrongly assuming I can run a 1987 4WD Blazer rally wheel on my ‘69 c10, for example). Thank you