adding an amp, tweets and such
 

i wanna improve the audio in my 2000 lt. i would like to run all the speakers off one amp. this would be 2 tweaters in the dash, 2 subs in the doors, and then one tweater in each rear door with one sub in each rear door, how many channel of amp would i need, and also i noticed when i had my back had trim panel off that there was a spot for speakers there, i was wondering it if would be possible to add some back there for when the lift gate is open and i wanna rock out.

thanks in advance for any info

with what you're talking about, the door speaekrs are not subwoofers, they are woofers.

The easiest way is to buy some component sets that have a passive crossover allowing you to run a tweeter and woofer off of one channel of an amplifier. In that case, you would need 4 components sets and 1 4 channel amp to power all of them.