1. Is it safe to charge the battery inside the trunk without removing it from?
2. Do i have to disconnect the + and - cables before the charge?
3. Has anyone done this, any feedback?
4. What would be the most economical charger that will do the job?
5. How long this takes?

I'd take it out..............Just because your gonna have to leave the trunk open a little to let wires run to the A/C current, and you could possibly trigger the trunk light.

The charger needs to create a loop with the battery to charge it. With the battery connected to the car, the charger is making the loop with the entire electrical system, not just the battery, and that can only be a bad idea.

Any trickle type charger I am assuming would work fine, and depending how dead the battery is, I couldn't see it taking more than 12 hours.

Why don't you wanna take the battery out?

Make sure you have your radio code if you disconnect the battery.

Ohhhh I forgot, Napa can quick charge the battery for you......it takes 20 min.