If I'm going to install 2 aftermarket amps to the Bose HU (bypassing the EQ of course) to power the 4 door replacement speakers - do I need to use a amp wire kit for EACH amp??

 

Depends on how powerful the amps are. I have a JL 300/2 and a JL 500/1 and I ran 4 awg from the battery and into a distrobution block. Then ran 8 awg into each amp. I use 8 awg ground from each amp ground at the same point. So, I am running around 800 watts. If you are below 500 total, you could probably run 8 awg from the battery but, more is always better than not enough.

 

i agree with AcuraX2, for cleanliness sake you may want to run a larger gauge from the battery to the trunk or whereever into a distribution block and then the smaller gauges. if youre running obscene numbers of watts, then double runs of wire may be in order.

 

Actually I'm only going to be running 65x2 to the front and 50x2 to the back...

 

You could get away with 8 awg from the battery and then just split it and run 8 awg to each amp. I would consider going ahead and running 4 awg. More is better and if you ever want bigger amps, you already have the wire.