For those who might read this post in the future, my backfire issue has seemed to clear up. I believe this was caused by condensation built up in the exhaust system from sitting for greater than a year. While the gas may have been a contributing factor. We'll never know because that gas will not be used in this vehicle.

I decided it was time to take it out on the open road. I took it out on the interstate where it handled beautifully. I then took a drive through town where it never once backfired. I've got a few new parts coming, primarily cosmetic at this point, a new radio, headliner material, cabin filter, air filter, and new front brakes. I've also got to take apart the dashboard to fix my center vents (that don't work)...I found a pretty good tutorial on that http://kropf.net/w202/Dashboard.html

Brian