RCA plugs on factory head unit?

Is there any way to hook up an amp to my 97 GT factory head unit? Are there RCA plugs?

go to any retailer and buy a line-level adapter. They are cheap and splice into your speaker wires.

Well, my amp will only be powering my rear speakers, so can i just splice it into my rear speaker wire or will I have to splice it into the wires for my front speakers too?

you can do just the rear