Isn't the position of the original torque tube axle forward of center a considerable amount?
I have 2 trucks which I have converted to open drive and used spring perches from classicparts.com. They have an extra off-center hole which I used to move the axle back by about the same amount that the offset was on the original funky rubber impregnated spring mount did.
If one prefers the wheel to be in the center of the wheel opening, I can appreciate that.
If conversely, one prefers the original placement of forward of center of the wheel opening, I can also appreciate that.
I am just trying to be clear of whether we are counting our apples/oranges in one basket before they hatch. (Now where did I leave my football bat?)
A few pictures would come in handy right about now.

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission