Anybody out there know whats the biggest wheel and tire combo I can run on my 79? Iwas wanting to put 20's on it.

20's should fit in your maro providing you get correct offset. I seen it done before. Tire size 255/35R20 or 245/35R20

Thanks for the info!
You wouldnt know where I can Get a gauge pod (pillar) for my 79 Z??

classic industries has it, check them out they have plenty of stuff for you classicindustries.com

Thanks Aaron. You guys are alot of help!