use a 2x4 scrap to support the back of the motor against the cab, not against the valve cover. after you get the top two bolts loose. if you use a u joint on your extension wrap some tape around it so it dons't flop all over.
dont forget the wires and speedo cable.
if you have the fly wheel turned make sure they also turn the step on it.
use brake cleaner on the bolts and blue lock tight.