If you're tightening the big ones that the tremolo rests against, those change the overall height, but will NOT change the angle of the tremolo. To adjust the tremolo angle, remove the back cover from the guitar (the square none, not the one that covers the control cavity). There will be two screws that hold a claw that holds the springs, which are THEN attached to the tremolo. Tightening these screws will increase the spring tension, which will lower the tremolo angle. This will also change your string tuning (strings will go VERY sharp), so you'll have to retune. This, of course, will AGAIN lower your tremolo angle, so it's an iterative process.
Try tightening the tremolo screws until the tremolo goes HALFWAY down, then retune. You should end up close. Then, readjust to get it where you want it. I like my tremolo to be level with the body of the guitar.
AFTER you get the tremolo level, adjust the bridge post screws to set the string height.
Schaller used to make a nifty spring hook that attached to the tremolo cavity, and allowed you to adjust tremolo spring tension from OUTSIDE the guitar, with a hex wrench. I have these on all my guitars, they are VERY cool and well worth the money.
Once you have your tension set, use the SAME BRAND AND GUAGE of strings every time. Changing brand and/or guage will mean you have to reset your springs just about every time. Changing tunings will also do this.