krj wrote in
:

Which one is "out" of the 4-108 that goes
to the "in" on the hot water heater?

I think out on the 4-108 is the one on the head. It's been a while. Why
not just hook 'em up to the water heater and start the Perkins. Which ever
one gets hot FIRST is the out of the engine to hook to the in on the tank.
You can always just swap the hoses on the tank if you got it backwards.

--
Larry