My marker light bracket broke on my 1988 Mark II. I ground the little bit left of the metal down flush. I located a light that came apart and allowed the bow pulpit tubing to fit within a round fitting on the light unit itself. Literally clasped around the pulpit. I used accordian type plastic wire shielding to cover the exposed two-three inches of wiring coming from behind the light for an excellent finish. No issues for the last four-five years. That was the easiest, most effective and most affordable method for replacement.
Bob
MarkII