I used to assume stuff would hold together for me to, then after walking home more than once, I figured it was cheap insurance to go through the rig in late september, pulling the undercarrage, if zerks dident take grease fix it so they did, looking for cracks and scrubbing off rust and OSPHO treat the rust and rattle can it black, I find that the OEM hyfaxes dont hold up as well as the graphite impregnated ones that Dennis Kirk sells the silvery black one's, I siphon the gas tank dry, into a gas can, swab the tank dry with a rag on a stick and Mr Funnel the gas back in the tank pretreated with some Sta-Bul added, drain the carb bowl, lube the cables, wipe down the primary clutch and tri-flow the parts that can be lubed, wear rods, stich up cracked cowling with tuna leader and soak it with linseed oil to set it, drive train i replace the bearings wither they need it or not (Arctic Cat) chain case I drain out and refill with fresh Turco.
I even use a suction gun and suck out all the injection oil till its dry then change the inline filter I funnel the mix oil back in through a funnel useing a coffie filter to strain the chunks.make shure the oil injection pump hits the marks, I see frame cracks and loose stuff while doing this, I even pull the engine and wipe it all clear under there, in short if you been in there it's not intimidateing to do the work, besides I'd rather take a couple days going through the snowmobile in the warm fall than when its -20F with 15mph winds out the north to finally replace the recoil starter rope, even work on the breaks.
I recomend useing a good grease that doesent set up like cement when cold, I like Mobil#28 synthetic grease, Shell #22 is another, Ive used Texas Refineing Co #TRC880 , I like castrol snomobile, Polaris is my next choice (lack of choice in town)
The fuel tank was hitched to a big sled we rented from Joe McCoy of Selawik AK, he had used the sled and his Alpine to move the big diesel AVEC generators from the airport to the light plant on the otherside of town, we hitched a Polaris wide track to the hitch, we used a couple heavy ropes and attached two Polaris 550 sport trails and we averaged 15mph the whole way.