Running like a champ

I finally got my 360 magnum up and running. I put in an electronic ignition system by Pretronics distributors. Its the flame thrower 3 system with matching coil. Mechanical advance. No more points to mess with. Runs fantastic was a little costly but, well worth the money. As soon as I find a 8.75 rear I can afford I'll be changing that next . I'm thinking 393 gears should work nicely. The 8.25 that's in it now won't last. Anybody have any thoughts I'd like to hear them. Remember this is a 66 Barracuda with the small bolt pattern and 13 inch wheels I would like to go to 15 inch in the back and leave the 13s in front