Does anyone with the mygig radio know how to first off get behinfd the radio and also if it is possible to wire it for amp ive done it before on other cars but had an aftermarket radio so was much easier any help would be greatly appreciated.

 

If you want to use RCA inputs for the amp you'll need to get two high to low level converters and tap into the front and the rear for the front/rear speakers

If you just want to tap them for the sub use the rear deck speakers and the high to low level converters
Then just run proper power and grounds to the amp and the RCA's