[alanwoodieman]

to cure this problem you will need to clearance the inner cap to fit the distributor body, the cause of this problem is the "swelling" of the soybean plastic that Ford used and the corrosion of the aluminum housing. I typically bead blast the housing to clean off the corrosion to help in the fit of the inner caps and have very carefully bead blasted the edges of the inner caps--saves sanding time.