The biggest issue I see with ANY water to air cooling system (4wd or not) is the line size and pump type. Personally I only ever run 1” hose with a 115LPM pump... if you drop back to say 5/8” heater hose you’ll need to run a $350+ high performance pump to move enough coolant.
And yes, you want a decent size reservoir and front heat exchanger (some sort of car radiator).
And yes, you want a decent size reservoir and front heat exchanger (some sort of car radiator).