Tune all your strings to pitch.
If they lift the trem too high,
Detune them slightly.
Add springs AND/OR screw them further in AND/OR change how they are placed (e.g /|\ is tighter than ||| and |||| is usually tighter still), checking to see if trem is pulled back enough (estimate).
Tune to pitch again.
If trem lifts too high/low again,
Detune strings slightly again.
Adjust trem springs accordingly again.
Repeat as necessary until trem is at the height you want when all the strings are at pitch.
Now check the intonation of each string. It's probably out.
Put a block in the back to stop the trem from pulling back. Adjust the intonation. REPEAT EVERYTHING AGAIN.
Then when you change your gauge again.
YOU GET TO DO ALL THAT ALL OVER AGAIN.
Ah the joys of floating bridges.