Ok so I know it's been asked before awhile ago.. I have a 2021 GMC Sierra 2500hd SLE without the 110v outlet in the cab and the bed, but the wiring is behind the dash for the plug to connect to. Has anyone added the plugs, inverter and switch to the dash yet? Is the inverter already there? Really want to add the oem setup to my truck if its possible. Picture isn't exactly my vehicle but you get the idea where the outlet goes.