system set-up, and pre-wiring for future growth

[ff6849]

My plan is to have 2-6x9 installed in the package try and a small sub box (8-10" sub) that will fit under the package tray and a 4-Channel amp, 2-Channels for the 6x9's and bridge the other 2-channels for the sub. With a mid level single DIN head unit.

Questions:
1. Has anyone else run this type of set-up, what's the good or bad
2. Car has no interior, car is at the body shop being painted, if I just want to install the head unit and the 6x9's  and than add the amp and sub latter  what pre-wiring do I need to install under the carpet to

[Bullitt-]

  That will work for the rear , exactly what I did. Be planning for a pair of speakers in the front of the car to make it sound the best.
Get a head unit with separate Sub Channel output RCA jacks as well as front & rear channels.

Start with an amplifier kit, that will give you the main power wire, remote on wire, & a pair of RCA cables
http://www.amazon.com/Research-PK8Z-Series-Amplifier-Installation/dp/B000P17ZHK/ref=sr_1_3?s=automotive&ie=UTF8&qid=1353686441&sr=1-3&keywords=amp+kit
Add a second pair of RCA cables for the Sub Channel
http://www.amazon.com/DB-DOUBLE-SHIELDED-COMPETITION-ADAPTER/dp/B004TOILKY/ref=sr_1_9?s=automotive&ie=UTF8&qid=1353686646&sr=1-9&keywords=db+17+rca

If not running an amp a pair of regular speaker wires from the head to the rear would be needed also.
 I recommend you just go ahead and get an amp & save the trouble of having to do it again.   I ended up adding a second amp (could have used a 5-channel) for my front kick panel speakers & located it in the trunk which necessitated a 3rd set of RCA cables as well as speaker wire to run back to them.

This JVC-KDX80BT does NOT play cd's but does a great job with i-Pod/iPhone, put one in my daughters car & it sounds a LOT better than the Sony & Jensen units in my other cars.  http://www.amazon.com/JVC-Bluetooth-Digital-Media-KDX80BT/dp/B0079LGNAO/ref=sr_1_1?s=automotive&ie=UTF8&qid=1353688020&sr=1-1&keywords=jvc+kd-x80bt