Keel bolt issue
Have to disagree with you Jeff. First of all the Catalina has a cast iron keel not steel. Tobin bronze is considerably more noble. Not sure that the bolts on that boat are hooked in a J at the head, but new ones can easily be machined from a rudderpost or propeller shaft. Second, if the head or J of the bolts are sealed properly, the will never see moisture and not contribute to any electrolytic reaction. Finally, only if you are using something like bronze or 304 active stainless will you be able to adjust the nuts and tighten the keel.