Here'* the deal, I have two speakers that I'm throwing up front. They're two 6.5" Infinity Kappa component system speakers that run @ 2ohms. I'm sure I don't want to run the fronts and the rears off my Pioneer in my sig because I know the odd resistance configuration is going to **** something off. I'm also sure I'd start getting distortion. My question is, is there a way to wire the front speakers to run off this 2 channel amp I have laying around, and get the rears to run off of the stock head unit? I really don't want to blow the head unit up, but I'm trying to do this as cost efficiently as possible.

If I can't run this with a mix of head unit and amp power, anyone have recommendations on a cheap amp I can use to run all four? Rears are stockers.

Your Pioneer head unit has 6 RCA preamp level outputs. One pair for front, one pair for rear, one pair for subwoofer. Just use the pair for the front to drive an amplifier for your front speakers, and let the head unit drive your rear speakers like it already does.

Basically, the head unit you have allows you to do exactly what you are wanting to do.

Alright. Running only the two rears on the head unit won't do anything negative due to it seeing strange resistance? What are the resistance on the rear stock 6x9s?

The stock speaker resistance is somwhere around 3 ohms, your Pioneer head unit shouldn't have any problem with it.