Honda accord 2013, after market stereo

New here and need help.
I have a 2013 Honda accord lx 4 door that I want to upgrade with my old equipment, JL xr651csi comp speakers, Kenwood head unit and alpine amp.
BUT I want to keep the stock radio as it has the backup camera and wife wants to keep it.
My question here is, for me seems to be viable to just cut the speakers wires from the back of the stock radio, rewire or use the speaker wire that comes with the car, and use the signal wire and feed the radio from the fuse box.
I don't know if that would work....?
I mean, if I just cut the speakers wires from the stock radio and feed the new head unit and use new speakers for the speakers front and back, would that be viable?
Should everything else work as it should? Backup camera?
I know that I would miss the radio controls, I'm not worried about that.

Hope that I explained my self.

Thanks for your help

Sit in the rear seat, look at the headliner 6 inches from rear and dead center of the car, is there a small perforated grill that could have a microphone behind it?

Thanks for your reply.

Yeah, it is in the ceiling, right in the middle

I’m ready to work on the installation of the amp with the stock radio and check how it sounds with just the rear speakers before I install the HU and wait for more tips about this process.

Thanks again

You need to disable that microphone and the one on the right side of the overhead console on the roof just behind the rear view mirror. If you disable the one on the left side of the overhead console your bluetooth will not work anymore.

This is going to be a very lengthy process.

Yeah, wife is not happy....who cares?
I'm not planing to use a subwoofer at this moment.
Would I need to disable those small speakers?
Or just go behind radio and unplug the ANC?

What do you think about what I want to do.
Just to cut off speakers wires from stock radio and rewire or re-use them?
Find signal and hot (orange) wire and hook up new HU?
Would that interfere with something with the rest of the gadgets?

Amp wire is ready, found this guy on YouTube and it shows where and how to go thru firewall, so far, easy.
Tomorrow I hope to finish with the amp installation and hook up rear speakers....lets see how it goes


Thanks for your time and help

Update,
Rear, front speakers and amp up and running.
It improved the sound, but still needs the upgrade head unit.

Just waiting for some help about if is good idea what I’m trying to do.