Rear suspension help!!!

[Erotomania]

Well, for starts, this is my first post. My name is Scott, I'm a full time worker/student, spent 3 years professionally doing car audio in a legitimate shop(best buy and the like count differently to us! ha) and I'm a pretty serious gear head, as most of you are. I've browsed this forum a decent amount, but there's tons of stuff, so If I ask anything stupid and already covered forgive me, I'm new.

Anyway, I've got an 2002 Prizm w/ 153K 3spd auto trans. It's my DD, passed on from my parents, we've owned the car since brand new. It's always been a great car in reliability. Only developing problems with mine is a bit of oil consumption, seems to vary a bit, but usually putting about a quart total in between 3K oil change intervals. It leaks absolutely nothing. Then the trans is starting to slip a tiny bit as it shifts into 2nd in low rpms under load, and all the time into 3rd until rpms get close to 3K.

Anyway, this is my DD. I know its horrible but I hardly keep it clean. I have a '90 miata widebody track car project and thats were I focus my thrills. As a DD, it does get all my car audio attention. So to the point and my problem!

The rear suspsension sags like hell. I've noticed they sag on their own in the rear. I've added atleast 100+lbs to the trunk. Yes its slower, yes milage is effect, yes it's got a rear weight bias on the handling. Kinda doesn't help my tranny issues. I can live with most of that. The rear sagging really needs an attempt to fix. So far none of the suspension has been replaced. I noticed recently on all 4 tires you can see the inside of the tires has been contacting the strut/shock where the spring base is. I also noticed, that whole spring/strut assembly is MASSIVE(Diameter)! So, I figure all of it could use a overhaul, but atleast the springs. The car drives well, handles pretty nasty bumps well, never rips the wheel out of my hand etc, which leads me to think the struts aren't gone yet.

My thoughts, OE spring replacement in the rear, AFM lowering spring in the front. Concerns to that thought: I see cars with lowering springs and the rear still sags, and I'd be will to bet they dont have the same weight in the rear as I do!

Aside from the appearance(I could live with it if it was purely appearance) you can feel the rear suspension is under load, and tilting the front higher, causing the front suspension and steering to act a little more unpredictable. Maybe AFM lowering springs in the front would put a little fix to that, I've also considered going to a 205 tire next time I replace tires(hopefully new wheels also. It currently has 195s, factory I think was 185, regardless...Real skinny and tall sidewall=lose handling.

I'm not a toyota guy, I don't know anything about toyota cars as a whole, so I'm hoping you guys will have some alternative ideas. I've heard of other car audio guys fabbing some kind of spacers to their rear suspensions w/ high spring rate springs(lowering springs). I've done this on trucks before in the front, leveling kits. Just a urethane puck between the upper shocktower mount and the strut/shock assembly. I have no idea if something could be done similarly to a prizm/corolla.

Converse!

Also a quick side note to avoid making another post, I've done a bit of searching but not a whole lot, I think over the summer I will do a tranny swap to a 5spd or maybe 4spd auto. I'd assume I'd need the tranny, shifter, clutch petal ass., reseviour and lines, MT tranny mount and the respective manual trans car's ECU. I've done trans swaps in hondas and seen it done several times. Do you guys have a perferred source for imported motors & trannys?