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There could be another issue if you replaced the booster and MC, in that there is a shorter non adjustable rod in that linkage (between booster and MC) and those do come in slightly different lengths. If you have the original rod off the truck, might try installing it instead of the one you used. Or, if you re-used the original rod it may not be exactly the correct length for the new booster/MC combo (it could be a bit too short - thus the pedal travel issue) especially if you installed a different type/capacity booster.

I have seen at least three types/shapes of boosters on these trucks - the C10s mostly seem to be all the same (smaller capacity and single diaphragm) - but on C20s and C30s have seen two types (double diaphragm - more effective) and it is among all of these that I think the rod length difference comes ointo play.
The difference in the length of those various rods is not much, but it does not take much difference to have an effect at that point in the linkage.

Don't ask me why this rod issue is so - it has confounded me more than once, and I do not know where one can buy rods of differing lengths. I try to save every one I see in case I need it some day.