First of all thank you all for your input and advice. I am now in the process of getting ready and i am wondering if anyone would have a recommendation on a heater, which ones are the best for an m-1009 and how many watts should I get?
Both my CUCVs had block heaters installed already so not sure what wattage they are. I think 600w is the 'standard' aftermarket one for a 6.2. Check the freeze plug on the drivers side just behind the motor mount; you may find you already have a block heater and someone just unplugged and threw away the cord. My $.02 is block heaters are better than tank heaters or radiator hose heaters because you're heating the fluid right in the engine, not heating the coolant then passing it through a hose where heat will dissipate, and then into the engine. But anything is better than nothing.
Oil pan heaters - I like the 100w pad heaters. I have those on almost all of my vehicles. Don't be stingy with the silicone installing them, especially around the edges. Magnet-mount heaters fall off. Guess how I know.
On both my CUCVs, I have the cords routed up the drivers side through the grille to a 3-way adapter with one outlet covered. If you have enough length, tie the cords to the grille guard - takes the strain just in case you forget to unplug before backing up. That's all you should need unless you plan to head up to the interior.
If you feel inclined to heat the trans or t-case (not necessary for Valdez temps), look at 50 or 75w pad heaters. Not as large a volume of fluid, so you don't need as large a heater.
The j-box and extension cord under the hood is a standard way to power multiple heaters up here. Usually the t-case gets skipped in favor of a battery heater. When I was driving my M37 in Fairbanks as a daily driver I had a 6-outlet power strip under the hood running a coolant tank heater (engine was pre-plumbed so I took the easy route), 100w oil pan pad heater, 50w trans and t-case pads, and 60w pads under each battery.