From the shop manual:
"Drain crankcase. Remove the starter motor, clutch return spring, and the flywheel housing front cover. Remove the bolt retaining the road air breather duct and remove the duct. Remove the bolts retaining the steering gear idler arm bracket to the frame. Remove the steering gear arm and drop the idler arm connecting rod until it hangs from the spindle arms.
Unscrew the oil level indicator tube. Remove the oil pan retaining screws and the oil pan. The two front retaining screws can be reached through access holes provided in the frame front cross member.
Note: On some engines it will be necessary to dis-connect the front engine supports and lift the front of the engine.