Sorry didn't see this, when my first alpine went in there was no harness available, don't know if there'* one out there no, there should be.
My install was all hard wired and spliced into factory wiring into the back of the ribbon cable, all speaker wire is new and had to be run the the trunk first before the front doors. get a wiring diagram for what colors to tap into. Pontiac Dad should be able to get you that.
First check for a harness, much easier than what I went threw. Oh and my mounting kit is off of a VW cause I needed a non flush mount. othewise the 01+ monte carlos have simmular dash demensions.
2001 SSEi 13.731 @ 101.59--->PICS HERE <---
--Intense PCM--2nd gen LSD--3rd gen Rockers 1.9 --#105lb springs--oil restriced pusrods--Intense shift kit--TEP CAI--ZZP mod 3.4/3.2 --IAT relocate--TOG silver ceramics--SLP CAT--o2 fake--160 stat--PRJ 10.4mm wires--Autolite 104'* @ .055--MAP TB heat shield
--Custom mesh grill--Cleared front and rear corners--Angle Eye'*--Silverstars 9006+9005+H3--PONTIAC 3rd break light overlay--Embrodered PONTIAC head rest wrap--Arrowhead inlays for front+rims+steering wheel--Zaino polish
--Alpine IVA-D300 7in TV--two 10W7s--JL amps 1000.1 & 450.4--MB Q'* 6.5in Comps--Optima yellow top--5 farad cap--lots of dynamat extreme--Custom install w/ plexi and mirrors--Sirius radio--compete in Sound Quality!!!
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