The Harpoon mod is so you can fill your diesel tank full without it foaming and shutting off the pump way before your tank is full. The Hutch mod I think is to stop the air from being sucked into the fuel pump from the fuel tank. Both mods require you to drop your tank. The Harpoon mod all you do is cut your vent tube off leaving a half inch or so left inside the tank. The Hutch mod Im not sure would have to do some research.
Last edited by vitalidle : 02-07-2007 at 06:47 PM.