Converting Mach 460 to Mach 1000

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Massachusetts
How would one go about doing this??

Are the head units any different other than the Mach 1000 having the MACH button instead of audio mute??

Could i keep my stock head unit and just add a toggle switch to turn the 1000 on?

Also, how would i go about adding the subs to the back? Are there stock harness plugs already there?

Or would i need to totally redo the setup to do this (which means i wouldn't do it)

I don't want to go aftermarket. I like stock factory setups and i was pleased with how the mach 1000 sounded in a friends car