bumper is rusty don't know be quessing rechrome is expansive , going to paint it. I see by looking at it 4 round bolt heads on it, is that what holds it on or are there more bolts, what do I need to take off to get it off?

The 1970 Pontiac Factory Assembly Manual would be your friend about now and they are not that expensive. Lots of exploded parts diagrams. There are probably two more bolts at the ends, at least there were on my 70 Catalina. I also had to remove the tail lights to get a socket on several of my bolts.

Rick

Should be 2-3 bolts through bumper bracket and frame both sides. Make sure you prop the bumper up with a jack (or something) when removing. It is heavy. Also un plug any lights if needed. Remove the bracket from bumper, after removed from car. Check into Chrome like powder coating in your area, if the bumpers are in good shape N not bent. Shop will probably ask you NOT to sand or mess with small dents and let them do restoration same if you go with chrome. Good luck. We want to see pic's! Didn't anyone tell you how much we like pic's??

lolI'm still learning how to post,pics are next!