Acura TSX install questions

I am researching how to upgrade the stereo in my Acura TSX and have stumbled on a couple things in the circuit diagram. The car has an in-dash molded head unit that really can’t be replaced. This feeds a small amp that drives the car’s eight speakers. I would like to bypass the stock amp and feed the signal into a preamp/EQ that would, in turn, drive a set of component and sub amps. Neither the HU nor the EQ supply a 12-volt remote turn-on. The constant power supply for both the HU and the stock amp are in-series through the fuse box. A 10-amp fuse then feeds the HU and a 20-amp fuse goes to the amp, both through WHITE/ blue wires. The ACC wire goes through a single 7.5-amp fuse after the ignition switch and then into both stock units through a yellow/red wire.

My first question is whether the ACC supply, with its 7.5 amp circuit, is stiff enough to supply the remote turn-ons for the EQ and the big amps. FWIW, the amp pin-out diagram calls the yellow/red wire the "ACC (main stereo power supply)" for the amp.

The next question is about the antenna. The diagram shows YELLOW /GREEN antenna power-supply wires from both the HU and amp. They are tied together and then go to the window antenna coil. Would there be a problem if it only got the supply from the HU?

If I do all of this I would use the amp constant supply wire to power the little EQ and replace the 20-amp fuse with the appropriate size. The new amps would have heavy-duty power and ground supplies. I will need to put an LOC from the HU to the EQ and will use RCA outs (Man, that’s a lot of acronyms) to the amps.

If anyone has any comments of suggestions, I’d love to hear them.

Thanks, Skip

I wondered about whether to take the preamp signal before or after the amp.  It shouldn't be a big deal to do it either way since they are only a few inches from each other.  Thanks for the input.  I'll put it to good use.

Skip