I have never seen the benefit of moving the solenoid or contactor box into the engine bay which then proceeds to bake everything inside it continually. And the contactor/relays inside are sealed so rain water isn't going to affect them.
For the control switch, I mounted a remote winch switch onto my dash in my previous TJ but having to hold my arm out continually while operating the switch was nothing I cared to continue with on my second Jeep after that Jeep was stolen. Instead I use the standard Warn remote control and simply run its wiring behind the radiator grill and around the driver's side mirror and lay the hand control on top of the dash. When I need to use it it's far more convenient to grab it and then hold the control in my hand than it was when I had the switch I added mounted on the dash.
This is how I did it on my last TJ and I wouldn't put a switch on the dash again like I did then.
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