[Meotchh]

Radio 12v= lt. green/purple positive radio harness
Radio Ground= black negative radio harness
Radio Ignition= black/pink positive radio harness
Radio Illumination= lt. blue/red (dimmer) positive radio harness
Factory Amp Turn-on= dk. blue positive radio harness
Power Antenna= orange/lt. blue positive radio harness
LF Speaker= org/lt. grn positive, lt. blue/wht negative radio harness or amplifier
RF Speaker= wht/lt. grn positive, green/orange negative radio harness or amplifier
LR Speaker= gray/lt. blue positive, tan/yellow negative radio harness or amplifier
RR Speaker= orange/red positive, brown/pink negative radio harness or amplifier

That should help. Sounds like you purchased the wrong harness adaptor. But since you started with the cutting go ahead & splice em.

BTW in case you have not noticed, the factory amplifier should be below the stock radio.