I’ve put Jeep between brackets because yes, it wound hard to fit a 4+1.  3+1 would « work » for that platform but not more. 
The thing is I don’t think that the 100% military spec vehicle is always necessary for everything on wheels.
		
		
	 
Not everything -I laid out where I think COTS systems fit.
  Duty Van's
  Staff Cars
  RSS/LO Domestic Rovers that see very limited off road usage.
The issue is with dedicated Comms, Weapons/Mounts, Electrical, Lighting, tires, and often fuel requirements, you get so far away for a typical COTS vehicle that you end up with a purpose built system anyway.
 The last decent  4x4 the conventional got was the 5/4t Chevy, in the 70's.
   *I leave out the CUCV 5/4 was from a USMC contract overage (due to USMC Hummer acquisitions) in the 80's that was acquired only in limited numbers for the Militia.
   **I also leave out the various CJ Jeeps the CAF bought as they where mostly MP vehicles and never acquired in any numbers, but also impractical as a GP Mil vehicle.
 Iltis - underpowered, narrow and too little space for more than 2 folks for anything longer than a weekend.  Set the bar for rollovers that even the TAPV has trouble catching...
 LSVW - the vehicle that failed every trial it went into, screeching brakes, and a fuel heater that liked to spontaneously combust, also to narrow a wheelbase - and due to height was tippy.
GWagon - narrow and tippy due to height, the turbo charger often clogged (at least in Afghan) and left it a limping dog.
Honestly in the space the CAF got 3 vehicle the US DOD had the Hummer, wonder what of those 4 was the best value for the $...
Yes the Hummer is fairly large, and wide - but you really can't tip it, and it's a 2.4t rated vehicle (don't load it like that off-road, but its fine for on road usage at that load).