Wall-E Wiring: Motor Circuit and Emergency Off Switch

I am in the process of slowly putting together the electronics portion of Wall-E. I am completely out of my comfort zone, but am making progress!

Today I succeeded with installing the 12v 60a battery to the components that will control the motors. Part of that installation included two solid state relays- one for each motor. These relays will allow me to have an Emergency Off switch (Deadman's Switch) from my transmitter that will kill the motors, but still allow Wall-E to have all other functions operational. This is an important safety feature; Wall-E is a very, very heavy robot, and a curious child wanting to touch his treads while he's in motion could cause a serious injury. Being able to make him immediately stop in case of an emergency is invaluable for me.

Many thanks to Mike Senna (@TheMikeSenna ) for the initial idea, Matt Hobbs (@matthobbs7350 ) for the recommendations to improve it, and Dan Coe ( @rendermandan2820 ) for being ever patient with all of my questions!