Rusted screw at foot of mast

[Guest]

We have a DSII with a tabernacle mast. The long screw at the foot of the mast, at the keel -- the screw that keeps the lower end of the mast in place -- is rusted and can't be moved. Previous owners left the lower part of the tabernacle mast in place, never taking it out. How could I remove the screw and replace it? Would you drill it out from both sides (the screw end and the nut end)? There's no nut, and the screw has broken off at the mast at the nut end. Thanks for any help.

Brooke (brookelise-at-attbi.com)