Good advice,i have used the same items for years,on piggy-back DC packs,and even on a few vehicles,where they provided an easy means of jump-starting or powering winches,etc. I even got quite tidy at sweating them on,with minimal damage to insulation. For demountable,heavy use accessories,these are the best option. :icon12:Get a proper fused supply fitted in the vehicles with an Anderson connector on it so that you can plug it in on each vehicle as required.
Andersons come in 50, 175 and 300A versions, or else they do smaller stuff in their powerpole range.