Well you have to decide turbo or supercharger first.

 

Supercharger seems easy to install yourself so that's what I'd recommend if you're on a 'budget'. I don't trust myself bolting on a turbo. Believe that requires an engine drop.

IMO, for what OP is looking to do, tires, RSB should be his main concern. He will actually notice those mods working for him. Exhaust, CAI/drop-in filters and a HFC or test pipes followed by a tune should follow. Then, I'd drop the car or look into rims if he's still looking to modify his G.

 

If you want a quicker car, buy Detroit. A lot cheaper in the long run.

 

Both aren't hard I'd you got the proper tools and skills. At the end you will still need to get the car tuned since pre tunes are generic