I am building up a '76 F-150 into a mud truck.  I am going to mount the radiator behind the cab inbetween the two rollbars and install electric fans on the radiator.  How would I rout the water lines and what kind of lines should I use?  What kind of water pump should I use, standard or clockwise? Should I use more than one water pump, like a main water pump and then a second electric one, or just stick with a high-flow pump?  All suggestions are appreciated, thanks.  

I saw this cool idea on xtreme 4x4 where they took exhaust tubing and routed it most of the way but used rubber hose for where you need to connect it to the radiator and the engine block. This would be the same idea as the brake lines......  

I would look for a source for some PVDF tubing (Polyvinylidene Flouride) It is kinda a super PVC pipe. It is flame retardant and very stable with aggressive chemicals (acids, alkalis, salts, alchols to name a few) It is strong mechanically and is fully rated to to 284 degrees F so high coolant temps will not be a issue. You could use regular PVC for return line if you wanted too. You could also use steel conduit that is designed for wiring in building too as it is fairly cheap, usually galvanized and pretty sturdy and stronger than soft exhaust pipe for impact damage resistance.  

summit has a kit for relocating rads to the back.