in my Scion FR-S there is an amp in the trunk that powers only the door speakers. the in dash mid/tweets are powered from the head unit. would the 50.4 be a good upgrade for this amp if i was also wanting to add a E8v4? the factory door speakers are 2ohm so that would put the fronts at 75w and in theory i could bridge the rears to be 150w at 4ohm. I'm thinking i could use the cars factory high level inputs into the front channel of the amp and use an LC2i to get a more correct signal for the rear/sub. does this sound crazy?