Yep, in the SM420, true 1st gear would be "granny" or "compound low." That's my parking brake. When I take off in it, I will slow to a stop before I can shift into true 2nd. Uphill would be worse. So true 2nd is my 1st, effectively.
For me, I'd try to use the gas pedal and clutch pedal to figure out how to minimize the buck. Right foot, left foot getting on the same page might solve the problem.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
