Alignment will not affect height to that extent. Going negative on most suspensions, if it were to affect height on a supra it would be lower the more negative the camber. What are your guys suspension setups consist of? going negative on the camber will handle better but will hurt off the line traction. Depends on what you want out of your car.
He bought his suspention about a month earlier.. his is a 93 with 75k miles and mine is a 95 with 94k miles. it has to be something like the bushings like you mentioned. oh well. it makes my headlights point down a lot now.
How long has the kit been on your car? the reason I ask is that springs will settle a bit. Maybe not a 1/2 inch but some. I'm not familiar with the RSR spring material and process. I know Eibach uses cold winding maching and superior metal so the spring will not sag. If the RSR springs are hot wound then they will sag some over time.
I know this is old but still trying to figure out why my drivers side is so much lower that my passenger side, I have changed the shocks, someone said ,maybe it's my bushing. The drivers side scrapes like crazy, i have 18 inch rims. I have Eibach springs. HELLLLLLP.