I'll be talking with the Best Buy installer again before the new head unit is installed this coming Sat. morning, but is this the correct way to run this? Here's what I'm planning on doing: They will install the HU, it has 3 set's of RCA outputs, & I'll do the rest myself. I want to run a 4 channel amp to the dash 4" & door 6X9's off the first RCA set, a 2nd 4ch to rear seat 6" (to be installed soon) & the rear pillar 4" off 2nd RCA set. The 3rd RCA will power a mono amp for the sub/subs, whatever I decide to do back there. Is this correct or do I have no idea what I'm doing here? Obviously I'm not very well versed in the stereo stuff so if there's a right way to do things please explain it to me. Question: What do you do you do if the head unit has only one RCA output? Or none at all? & you want to run amps.