I want to put in a nice double din that's cheap but def is nice. And some system in back.

Any ideas?

What car are we talking about here? 3rd and 4th gen Firebirds are 1.5 DIN and could be easily modified to accommodate a 2 DIN head unit or radio and still look factory. A first or second gen GTO/Firebird/etc. are 1 DIN and would not work well without major fab work to the dash and are generally not worth it. You'd need to buy a single-DIN head unit with a screen that flips out or hangs off the front.

Perhaps a simpler solution might be to get a Bluetooth car amplifier, use your cell phone or tablet as the "head unit" (which has Pandora, iHeart, or iTunes on it) and wire your speakers to the amplifier. Then you have a factory radio in the dash and a hidden sound system.

That's my opinion any way.