Hey man, try to get that bad boy off nice & clean. That looks like a factory original hanger and if it is, you can get some $$$ for it, especially if it's on the drivers side. I had to look high & low for one for my 69 and I think I paid close to $100.00 for an original. Your trash may be someone elses treasure. Especially in the restoration world. BTW, it should be bolted to the frame with (2) bolts.
I bought a set of those for my 67. I paid $100 for both hangers. I think I paid too much but where would I get them but one of the Cougar Vendors. I used them on my 67. They clean up real nice w/ black powdercoat!