Well the T/A was in the shop yesterday for a new exhaust system and brake adjustment. The back brakes did need to be adjusted but the mechanic said the popping was being caused by the differential. He recommended replacing the fluid so that's next on the list.
The mufflers were bad which I knew but the pipes that were on it also looked like swiss cheese.
It's been out of alignment since I purchased it in 2007 so I had them go ahead and do a full four wheel alignment on it as well.
It's ready to go to it's first show now. Might hit up the Niftee Fifties show in Spring, TX this Saturday.
Thanks again for everyone's help and suggestions!