andy,
That is a really nice score! I delaminated one of these badly cataracted CRT's last summer in my RCA, CTC-20 successfully so it can be done. Just be careful and wear eye and body protection. Your's looks great emission wise.
I have a 1966 Philco and the chassis in it has boards that resemble RCA but the main board has a quadrupule diode tube on it that I've never seen on an RCA color set. Here's a picture of my Philco chassis. I don't have the model number handy. Sorry. Here it is with the back off. I got a little over zealous with the compressed air when I was cleaning it out and accidentally damaged the tube layout sticker.
This one has the 21FBP22 so no chance of cataracts. The CRT is like new.
Rob