Can I snake the remote switch lead through the firewall, zip tie the wire so it doesn't move around and leave it unplugged until needed? The control box for my Warn winch is mounted in the engine compartment on the passenger side.

This would allow me to run the winch from inside the truck and not have the remote switch lead going out of the hood and in through the window. I could leave the switch and excess lead wire up under the dash or under the passenger seat.

 

Sure, but you would probably want a spare controller for those times when you want to run the winch from outside the truck. Like when you are tetering on a cliff or re-coiling your cable.

Or just hook up a momentary DPDT switch and wire it directly to the solenoids. Very easy mod. Here's a write-up in the Tech section:
https://www.yotatech.com/~corey/tech.../transalper.htm