I have seen many threads/post on stereos. However I don't recall seeing this one. Has anyone ever installed an aftermarket unit(Head, Speakers/Amp ) by running all new wiring just using the factory wiring for power/ground/antenna up/down and possible steering wheel controls? My thought process is use the existing power/ground wires, the ant up/down remote wire and possibly the steering wheel controls(knowing that I need the adapter unit). I would like to use external amp and run wires for that an all speakers. Would that cause any issues with the other electronics in the car? If this is possible could I them remove the 6 disc changer and Alpine amp from the trunk and just leave the wiring in? If this has been covered before I couldn't find it.
Thanks again.

 

According to the 2000 MY electrical guide, speaker wiring is isolated past the amp, so rerunning wires or anything wouldn't affect the other electronics. You might be able to get a reverse wiring harness that plugs into the speaker harness in the back (the one that goes to the Alpine amp) and have your new amp drive that. I'd look into car audio sites and see if any of them sell one.

There's not really any reason to rerun wiring unless you have problems with all the existing wiring, really want to relocate your external amp from the trunk, want to rearrange speakers, or plan on running unusually high power to the drivers. If the wiring is good I'd do a reverse harness and pull out the Alpine.

 

I reran the wiring from my new Clarion head unit (18 stranded/shielded) to the trunk where I installed an Alpine F240 (yeah its older, but it works nice) and used the OE wiring to the speakers about 5 yrs ago. I soldered in a quick disconnect and used heat shrink to cover. I used the Jag electrical guide from jagrepair.com to get the colors coordinated.
I replaced the door speakers with Rockford Fosgate R165S's (Crutchfield), I didn't install the tweeters (yet).
About a month ago I went after the sub and found it was toast. So I went and got Earthquake Sound SWS-6.5X 6.5-inch Shallow Woofer System Subwoofers (Pair). They are very shallow and will fit back into the space above the fuel tank. I'm not looking for a tub thumper, so these will be ok for me. You would be best to use say a piece of lexan or MDF with the mounting pattern of the old sub, cutting out for the new one and then securing one of these to it and fitting it in the same hole if you want to go that route.
But I am going to try something a little different. I am going to see if I can use both subs and reflect the bass back up toward the vacated spot to get my sound. I am building an angled mount, using lexan (MDF if the lexan fails), and mounting it to the bracing under the upper trunk lip. There are 4 rivnuts already mounted there and I'll insert a few more outward. I have 5/16" dense rubber mats I am going to using to trim the sub mounting area to reduce (hopefully eliminate) bad vibration for good bass. I'll have to update this later after I get back into town to work on it again.
Anyways, also a month ago, I replaced the 18 gauge wire with RCA runs and my sound improved immensely.
On the premium system steering volume, I found that Jag replaces the white wire with red stripe, but I haven't pulled the column apart to trace it. I will attempt that when I replace the bucket.
I got a new bucket for the head unit to sit in (from England), I'll get that part number on site also to help others. Its made for single din and is supposed to be a direct replacement. My OE one is dry rotted and the screw ears broke off years ago and it doesn't sit correctly.
I'm a contractor and out of town for at least another week, I haven't even seen the bucket yet, I just know its there from tracking.

The flip up panel can only come out when I'm in N or D. I usually leave it out.