We had to remove the wooden screw plugs hiding the screws in the teak trim in the galley, remove the trim piece then remove the screws holding the ceiling to access the 2 nuts holding the mast step. The easiest thing would be to drill out the step screws, knock the bolts down (yes they'll be there not captive but I cant see where they would hurt anything...they'll most likely roll to a low spot where they'll remain), tape the anchor & steaming light wires and plug the holes.
You will need to think about where you'll mount and pulling wires to your now-removed running lights!