66 barracuda

I bought it after it sat for 13 years. Today, after a couple of days replacing this and fixing that it starts and runs by its self! It smokes a little but sounds strong. Still a few things that I need to do to it but I got it running. Put it in gear and it moves forward and backward. Now what to do? Should I build the 273 thats in it or put the 360 that I want in it? How do I get bigger rims and tires? Whats involved in changing out the drums, can you do that? What kind of rearend should I put under it? So many queastions and I just dont know enough to make those decisions alone. Any help would be great! I hope someone reads this and responds.

Skullz