[JensR]

> "WAAY OVER MY HEAD".

Sorry, didn't know how to say it simple.

But it seems you already got the relay, and you are also very short for space, so my point was moot.
But allow me to rephrase my previous comment for completeness:

You know how a normal stick moves continuously from one extreme (-100%) over neutral (0%) to the other extreme (+100%).
If you have a two-position switch, it does not go continuously from -100 to 0 to +100%.
The switch only knows two positions from this range.
(A three-position switch should know three positions.)
If that switch in your radio knows -100 and +100, you can simply plug an ESC into the receiver. The ESC will be switched to full forward or full backward.
If however the switch knows only 0 and 100%, you might have problems:
Certainly with the ESC and maybe with the relay:
The ESC could then only be switched between standstill and forward.
For the relay it depends how it is designed.

Good luck!
Jens