Just bought a 79 GMC

[LeatherMan69]

Well Bought a 79 GMC 4X4. Doesnt need much... its going to be my daily driver. Even though gas is 3.15 where i live right now. My question(s) is i want to beef the tires and possibley the rims a bit. BUT i dont want to go huge lifted up monster i just want a nice stance with some beef to em to, i dont know "stabilize" the ol' girl a little better. She's just a half ton with manual lockouts so i guess my question is what would you guys recomend as far as tire/rim size to give it a bit more umph without going overboard...

Also since this is going to be a DD. I was wondering cause i havent done much research on it, but have heard the 'romors' for a lack of a better word. But does changin the exhaust help out with MPG's and i was thinking of a K&N air filter... obviously not a bad idea anyway.. but any more sugestions on the MPG increasing problems?

Sorry no pics as of yet. hoping to fix us a few rust spots, then paint her.
two tone black and metalic camel (stock color)