Selection of a body after mkt rims?

Coincidently I was on the phone and email with CenterLine Wheels most of the day yesterday. Number one they have great technical support. Unfortunately, I don't think they make custom wheels since they did not offer that to me. I need more backspacing on the wheels I was looking to purchase.

I love solid polished Centerlines and if I want them I will have to have a pretty narrow wheel since I am using a B-Body rearend in an A-body.