[A/S] 12v Accessory wiring (vehicle)

[CaptJetSki@xxxxxxxx]

I know this a little off topic of the Airstreams but we just got a '98 
Yukon to pull our 31' '71 Excella and at other times a '19 boat

I want to put a 12 power outlet in the rear of the Yukon to run a 12v 
cooler/warmer, a 12v spot/work light for hooking up in the dark, and 
a Power winch for the boat and. 

Im thinking the best way is to put a fuse block/circut breaker on the 
firewall in the engine compt and then running the power wire to the 
rear terminating either in another fuse/circut breaker or in a 2up cig 
plug, grounging in the rear. 

Any comments/suggestions ?
What size wiring?
What size fuse/breaker.
                    
Thanks
Tom (Captjetski)
WBCCI 12069