You can do the job from the bottom w/o doing anything with the starter. The bowl on the prefilter takes a 17 mm socket. Use a swivel head socket wrench or a wobble extension and have a bucket ready. The bowl is full of diesel and unless you want a bath you need to keep your face to the side. When you get the bowl off you can remove the adapter that holds the fuel heater in place with an 8mm allen wrench. Don't try to use a socket with an allen end because most likely it won't be long enough. Use the allen wrench with an adjustable wrench or a vise grips on the end of it. The adapter is in there pretty tight. There is a plug in the side of the fuel heater that needs to be unpluged to remove it. IMO you can throw the heater away because it's a troublesome POS and is really unneeded. If the old gasket from the pre-filter is in good shape re-use it, if not, order a pre-filter service kit from Cummins (FleetGard # 3845400-S) which includes a new gasket, new strainer basket, and the stamped nut to hold the basket in place. Don't try to use the gasket for the preheater on the prefilter bowl---it's too small. An easy job after you've done it once. Sorry if this is a lot more info than you wanted or needed. Good luck!
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