Procomp and Rough Country knuckles

Does anyone know if the knuckles on the ProComp 6” and Rough Country 6” are different?

ProComp requires 18”+ wheels and I met a guy the other day that is running 17” wheels with the RC knuckles. Wondering if the knuckles are exactly the same or if there is a slight difference in the RC’s that will allow 17” wheels with a specific offset to be run.

Anyone had them side by side?

 

Willing to bet it’s a wheel offset difference that allows the 27s to kind of work

 

agreed. I don’t think just any 17” wheels will work. I’m sure they *say 20” because just about any 20” wheel is going to work.

I’m just wondering if there is a physical difference in the knuckles that would allow one company’s knuckles to work better with a 17” wheel than the other company’s.

Anyone running 17” wheels with a 6” procomp lift??