In normal worlds, I can force a on/off state with a simple contraption like so:
----||SP|
|OF|SH|
SP = sideways spring OF = On/Off switch SH = Shell with the color of the block I want to force on the square
This contraption works by immediately killing off the shell if the color I want is active, and triggering the on/off block then killing off the shell if its not.
Unfortunately, I can't do this in 3D world because red/blue switchable blocks do not exist, so is there another way to force the on/off state with a contraption?
I need to be able to specifically set it to on/off, not just a toggle.

