Thank you for the reply.

As far as I know the body mount screws are longer with a coarser / wider pitch for better grip.
The lens mount screws have a much finer pitch and are about half as long.

Does someone here know where to find information on Pentax screw sizes.

I am especially curious to learn what size and pitch the screws are that hold the bayonet of the DA21/3.2 discussed here.

A lot is written about lenses but so far I have not found any resource on screw sizes used in Pentax lenses.

Thank you so much!