67 c10: can i use 1/2 ton springs on a 3/4 ton lower a arm

[fortytwo]

Howdy,

67 1/2 ton c10 2wd frame is shortened, l6 292 not built yet, muncie 3 speed on the floor.

I plan on doing one of 2 things either leaving the truck stock height and upgrading the front to 88-98 spindles brakes etc, or getting the 88-98 lift spindles. Either way my right coils are both cracked, so before i reattach the cab frame mounts and cab i need to replace my coil springs in the truck. I will do the springs so i can make a decision on the lift.
I want lift but dont need tons, in a different thread the formula for using these lift spindles are to use 3/4 ton lower a's and 3/4 ton springs. They also use 88 ball joints and inner and outer tie rods.

Is there any reason i cant use all 1/2 ton springs? Is there a reason i shouldnt go progressive? I would like to not have a ride like a lumber wagon.
Ed
FortyTwo