did 35 ford trucks come with a parallel rear leaf spring set up? Are these them? Looks like a spring over axle, the pinch bolt has a square head and the nut on the other end is a long one with a grease fitting
I've done a couple 35/40 pickup chassis using Chassis Engineering bolt on parallel rear spring kits with 8 & 9 inch rear ends. I use the light duty kit.
On my '38 Ford pickup (same basic frame as your '35, I got the leaf springs and torched the spring hangers off an '80 Isuzu pickup (Chevy Luv was same animal). Hung a Camaro 10 bolt on the Isuzu springs, worked well.