I wanted to free up some room above the motor, and didn't like the heat the in cab tank generated in the summer. I have a Swiss Troop with the tropical cooling system, which has a larger radiator. I don't know what effect this mod will have on the stock system.
The Mog has a wax thermostat external of the block, and also has an external bypass. The bypass allows the coolant to circulate in the block bypassing the radiator to allow the engine to heat evenly and quickly during warm-up. This is the fitting on the top of your thermostat. This bypass was routed thru the tank in the cab, so mucking around with that plumbing can lead to the early demise of your engine from uneven warming.
I tried to utilize as much of the stock system as possible, and keep the routing of coolant flow as stock as possible. Total cost of this mod was under 20 bucks
This is the u shaped pipe that runs behind the generator. The center section I cut out is where the bypass went in. The piece to the left is where the coolant enters the block and where the heater line goes back in. I flipped that over so instead of flowing to the rear of the vehicle over the generator it now flows forward. The bypass (center) section was added after it pointing up towards the thermostat at the front of the cylinder head. I then used a 90 degree straight down to the outlet of the radiator.
The parts numbers for the hoses are 71586, 71365, and 71446. I picked these for the diameter and the number of 90 degree bends I could cut and use. 
This series shows the assembly of the parts as they will go in the engine bay. I've decided it is to be called the engine bay. I thought of engine 'room' but decided it was too ostentatious and think 'bay' is sexier anyway. Note the bottom elbow faces away from the radiator.
Making the final turn into radiator. Note the pitcock to drain the system Now for the topside plumbing.
This wye or tee was cut from the plumbing above the engine. A 20 inch flex hose was used to attach it to the bypass fitting by the generator. The thermostat was angled approx 30 degrees to match the angle of the pipe and then used a hose elbow and the plastic filler neck cut off of an import car's radiator. Routed the overflow line to a fill tank from another import and I was done.
Works like a charm and have had it running without a problem, when the outside temps were in the mid-90's.
