That is my car that Shane linked you to. I like the style allot. And I think it would look great on an Olds or Buick A-body. My rear adapters are 2.125" and the fronts are 2". But my front setup is not very stock. So I would double check the size for the front.
The OEM wheels are worth far mor than the aftermarket wheels.
I sold a set of new OEM GM Z06 wheels online last month and I didn't think we would get much over 600 for them because you can buy replacemnts cheap... but I end up getting 1600 for the set.
I went with the imports (replacement) wheels. One day, when our bank account has recovered a bit, I think I will get a set of "nice" rims. For now, these will have to do. They do look nice though.