I'm not trying to sound rude or anything and I'm kind of in a rush to write this before I get to work.

You say you have 2 BPs and a 6.5' Red Tail. How long have you had those snakes? It might not seem like it, but a jump from that boa to a burmese is pretty substantial I'd think. 1.5' difference isn't just in the length, but the weight, muscle, and personality.

I'm with a lot of other people on here. If I were you I'd take it back and get a baby. If you can't take it back to trade for a baby for any reason, try to find it a good home with someone that actually has experience with larger snakes and knows what to expect.

You're best off getting experience by raising your own while handling the larger burmese as a volunteer with a local breeder or something.

Whatever happens, play it safe and know when enough is enough. Everyone else here is just as concerned as you are about what your situation is. Your actions do have a chance of affecting the rest of the herp community in this circumstance.

Good luck!