The rimblow, tuff wheels, 68-70 B-body steering wheels, 72-74 E-body steering wheels were all done pretty much the same. They are a stamped steel, then plated in copper, dull nickel, then chrome. Once the chrome finish has been damaged, there is no way to save it without a complete refinish. There are some that are replating in chrome but they're still not quite right. I have been through several plating companies and only one of them has produced an acceptable finish, but turn around is horrible.
If you're planning on painting, be sure to remove all of the old chrome, nickel and copper, then use professional paint and body materials and you should get nice results. I've used a nice automotive finish that is undetectible at 3 feet, but it is a paint, not chrome so you have to treat it as you would your car's paint job.
Good luck with your project, and if there's anything you need, feel free to contact me.
Dave