Stereo Upgrade Questions-2005 Tts Cab Most/bose

[sg2100]

Hello all -

Recently bought a 2005 TTS Cab, with GPS/MOST/BOSE speakers/BOSE AMP and have spent many hours researching the best way to upgrade the stereo unit - I plan on installing a new double din headunit and a new amp, but I'd like to keep the factory speakers <at least for now>. I haven't been able to find a lot of detail for an install with this particular configuration, so I was hoping someone could help me with a couple of questions:

1) I have not been able to find a wiring/pin out diagram for this particular configuration - anyone have any details? A long shot, but any chance a wiring harness exists for the amp side of things so I don't have to cut up the factory wires?

2) By my count, I have 7 or 8 channels (dash 2x, doors 2x, rears 2x, sub pass foot well 1x or 2x) - all of the references I've found seem to refer to a 6 channel amp. Do I need to support 7+ channels?

2a) If this is true, most amps I've seen support 6 channels max - so I'd have to get a separate amp for the sub or one of the pairs. In this case, any opinions about running the rear channel directly off of the headunit so I can support the fronts+sub via a 6 channel amp?

3) I've seen posts referencing the issue with the sub possibly being wired in a 1 ohm configuration - is that true in this case?

Thank you very much.

[OU Targa]

Just did my double din and new amp, researched for awhile and although your post is old, my thoughts:

(1)Leave the old wires in place, you'll have a new amp anyway so RCA's will run from head unit to amp, use can tap into the speaker wires, no need for a new harness, it will come with head unit

(2)I got a 6 channel amp but you will not have to replace speaker wire except one minor change, the doors and dash should be connected in your current config, my installer ran new wire to dash as those are easiest to reach, 6 channels for three pairs of speakers, my sub is not hooked up as it was 1 ohm and small anyway, would have to run a separate amp or combine rear and door on same channel, so I was told. For now elected to upgrade sub in the future.

[kato1453]

I found an install on You Tube where they put in a Kenwood headunit and kept the Bose speakers. You have to add crossovers to get the Bose speakers to work.