I have an SE and it only has the 5x7'* or whatever they are in the front and the 6x9'* in the back. I recently got some SSE or SSEi rear speakers with the whole panel and cover and the little tweeter and after I connected everything it seems as I have lost some thump in the rear. This is most likely due to low power right? I'll have to rewire everything as I did a terrible job and was just trying it out so maybe when I get everything fixed it will maybe sound a little better. Oh and mixing red and black doesnt really matter on speakers(not subs) right? Cause I tried both ways and I still heard the same quality sound so I just hooked them up however. More questions. Can I buy an aftermarket tweeter that will fit in the same exact square spot as the one in the back to where I can just screw it in or will it have to be one of those small round ones? I want to just get some good 6x9'* and a good pair of tweeters and hook up an amp so that I get my thump back.

Switching the red and black leads makes a HUGE difference!!! It sounds like you have one speaker hooked up backward. Think of it as playing the speaker backwards. It actually cancels out the sound of the other speaker. Looking at the speaker upside down, with the terminals facing down. Then hook up the red on the right lead and the black on the left.
Im not sure about the tweeters but you are better off putting good aftermarket 4x6 speakers in the dash. The front is what is important for good sound.

Yeah I always had the Left Black Right Red thing in my head but I wasnt sure how to apply it on these speakers because I got confused. Thanks a bunch for the help!

When you hook up speaker leads opposite, they just play opposite. A free air speaker like the 6x9 wont be affected, as long as they're BOTH hooked up the same.

The SSE speakers don't last nearly as long as the premium sound SE'*, and they generally don't sound as good.

Well the only thing I took from the SSE as far as speakers go is the tweeters which are inside the speaker cover. The 6x9'* I have in there are from a 1999 Grand Am which I used to own. And the front 4x6'* are aftermarket Pioneers.

the SSE SSEi speakers were designed to operate with the factory gain control amp. the SSE i speakers have built in subs...that makes the diffrence! the speakers should have 2 prongs on each side one side for speaker frequency one side for amplified bass signals.

Well the 6x9'* from the Grand Am sound really really good and produce noticeably more bass than these xplods I used to have in there which is why I switched them out. Ive been to lazy to reconnect the speakers because my car is a mess and all but I plan on getting it done today since Ive started the day pretty early and I also need to change the oil pretty bad. My cars been a bit sluggish for a couple of weeks since there is a big car door in the trunk and a bunch of junk in the back and Im 200 miles past my oil change mileage which wouldnt be so bad but its my first run on synthetic so I think it got dirty faster with the old dino stuff being eaten away. Well anyways, thanks for the help!

Got everything hooked up right and I am so loving it. Sounds amazing, especially in the back seat. Looks pretty good too with the premium sound speaker covers and black rear dash fur. Thanks for the help guys!