I am gearing up to swap in my SM420 to my '65 C20 Crusty Biscuit. The transmission has sat for a few years, a few, more like 16 under the eave of the house on the back patio (covered). It had a cover over the shift tower to keep dust and dirt and water from getting in there. I have read on here to pour kerosene or diesel fuel in there if a transmission has sat out in the open. Would it be beneficial to do that and turn the input shaft with a drill? Basically fill it, shift it into each gear and turn the input shaft a few minutes in each gear and repeat a few times, then drain out the fuel, and pour in the 90w mineral oil? Even if turning by hand, would this be a good idea before installing it?
