Threw trial,and error,and almsot giving up to the point of just re doing the whole thing with new hardware,i finally figured it out.
For those of us that have the Mach 460 sound system know when we try to put an aftermarket deck ourselves,.....cause we are do it yourselves type of guys.....,it will not work with the factory amps without a fight.
Well after lots of interweb research,i finally found the right harnesses.It's been 2 years of not having my Mach 460 system working,but i finally got it done.
Anyways,and this is not promoting another company in anyway seeing we have a site sponsor in this area,which is called Selective Sound.
What i found is that we need a special adapter for the Mach 460 system to make those factory amps work.
Threw my search,guys would use a harness from a place called Metra,and others would use a harness from a place called Crutchfield.They both specialize in factory adapters so you can adapt an aftermarket deck to your Mach 460 system.
I myself went with the Crutchfield.Lots of good feed back on there product.
So what you need (part #'s are from Crutchfiled)....
'89 to '00 Part # 120705510
The 2nd adapater in the kit has 4 RCA hook ups that are required.

'01 to '03 Part # 120705519
The 2nd adapter has 2 RCA adpaters,two blue wires with white stripes for amp turn on,and two black wires with white stripes for amp grounds.

'04 Part # 120705521
The 2nd adapter has 2 RCA hook ups,and two blue wires with white stripes for amp turn on.


The first adapter is your typical wiring adapter for the power,battery,ground,front,and rear speakers,and dimmer.Now depending on your deck,they will all have the solid blue wire for antenna control lead for the motor,this is what the two blue wires with white stripes will hook up too to have power to the amps,but if the deck you have or get is like mine was,and has an extra wire that is blue,with white stripes,then this is what you will need to hook up too as this is called external amplifier power lead,go figure LOL.This is where i had to trial,and error it.Cause of all the web search i did,no others had this blue with white stripes wire lead,and they just used the solid blue with great success.
Anyways,thought i would puit this out there to save anyone else a headache for when they plan to do a stereo,but want to keep the Mach 460 system.
I think this will work for most.

 

good writeup mine came with all the right plugs to keep the OEM amp but went full custom in the end. its kind of interesting trying to get it work..

 

Thanks Crafty.
When got my deck,and asked for the plug kit,they just gave me the basic plug kit,and i thought nothing of it until after it was all hooked up!!Sounded like !Tried a few different ways to get it to work without success,so i just ended up wiring the deck directly to the speakers,which sounded better,but it still was missing that kick!So with a lot of research,i finally found the above info,and put this together.

 

Damn me and electricity = NO WAY lol. Good write up laddie

 

Thanks!!
I like the challenge with the electrical of any sorts.

 

Great job 1LOW. You're gonna save someone quite a bit of time with this thread!

 

Thanks VAEM,that's what i am hoping,cause it's a real pain in the *** to work with the Mach sound system for the do it yourself guy/gal if you don't have the right stuff.