new door speakers in jeep

i jus bought a 96 jeep grand cheroke, from a car auction. it came with a huge doube din alpine deck and 6 inch crystal mobile audio speakers in all four doors. i put my sub in it. it sounds pretty good, but the deck doesnt even have sub pre outs, just front/rear. the 6's are hooked up to the stock amp under the back seat and they dont sound that great at high volume. is crystal audio any good? i plan on replacing them and getting a new deck. which should i do first? should i stick with 6's?

I would ditch the rear speakers, get a 4 channel amp thats like 50-75 watts per channel and has a built in crossover, and a decent 10" or 12" sub.

i have a Pheonix gold 12" sub in the back. should i get new 6's? or make kick pannels and go with something different.

try putting the 6's you have in pods

wheres the best place for them?

pods are normally put in the kickpanels

do you know any websites that could help me make them?