Rear bumper bracket solutions?

[84chevyboii]

wondering if I can fit a maybe late 70s early 80s Chevy g10 van rear bumper on my 84 c10 longbed, looking for bumper brackets, I ordered a set of stepside ones but no luck

 

[Craig 85]

I know for sure the van rear axles are wider by about 4", which makes me believe the van bumper is wider than the truck bumper.