I have found that the fit between Lee's 6-cavity mold blocks and the mold handles has too much play which allows the the rear-most male alignment pin to miss the female side and strike and deform the opposite mold block. It occured to me that if set screws were installed, one could adjust the play to the point where the male pin could kept in better alignment with the female side and could reduce the chance of buggering up the mold. It is idea that seems worth investigating.
The modification seems to work fairly well despite the fact that the set screws seem to like to move and loose adjustment (however, that can be fixed).