[mikegett]

No. Factory cars don't use rca cables. The cost is too great and limits flexibility to interchange parts. They will use the same low level signal that a rca uses in some situations. This use to be seen in high end luxury sedans but has been introduced into midrange HU's over the past couple of years. If your car is 96 then it will almost deffinately be a high level speaker wire. Only about ten percent of the HU's we made last year used low level in toyota. GM will be the tricky one starting in 05 and 06 with the digital data bus. To be possitive you can check the wires with a volt meter. I just don't think that you will have that problem with that old of a vehicle. Once again, ensure that you have a amplifier. Then remove the rear speaker wires from the amp and send them to the new 6x9. Test it out with the radio on low. If the sound is worse, or even the same, then have a radio shop ensure your connections. I know little about infinity amps. I will assume that they are like the monsoons bi amped. However, there are some amps(like the bose) that you need a dedicated Line OUT Converter to change the head unit ground. Othewise the HU and speaker can be damaged. I am sorry about making this complicated but sometimes there can be many variables to deal with.