yeah i think i could make it work, no interior in it atm...just two seats, no panels or anything...so easy to work with...i think current box is ~5 cubes..and i still got room, would just have to build it not quite as tall...hits back window on the slope...but i can always build into back seat area too..since there is not 1, and wont beget 4 type Rs and then another kicker 1200k, or just add 2 more P3s and amp. do you got room for 8 cubes ported for them?
Not going to be a drag car...dont plan to take it to track or anything...but motor is going bad anyway, if i am going thru time of swap, goign with a 302...still be a fast little shit...the car weighs right at 2000lbs...add 500-600 and a 302...and u still got mad power for a little car...stereo stuff is HEAVY. i would be suprised if you could get 150db without adding 400-500 pounds to the car. i suggest you build a pinto drag car and put your stereo in something else.as far as equipment goes, how about getting 2 audioque hdc318s and another kicker 1200 amp.
so if you said you have 6-800 for subs, i say sell both p3's and that should net atleast: 200, so thats $1000 for subs and another amp
drop 588 on 2 HDC318's right now shipped http://www.audioque.com/aq/order.htm
find another zx1200 in the classifieds, >$250 later
subs+ amp= $838
your gunna need about 10 cubes net tho and lots of port area
2 runs of 1/0 knu wire runs about 150 with blue wave fuse holders... and you'll in all likelyhood need another batt in the back.. so 1-150 for that found in the classifieds or locally..
the box is gunna run a mimimum of $150
so, in conclusion, about $1288 will do the job with pretty good electrical.