Cheri- I just measured it when I got home from work. The width of the keel stub where the pivot pin goes through, on my 1981 M15, is 4.25". Therefore, I'd suggest a pivot pin of 3/8" stainless steel bar, 3.75" long (to allow for a 1/4 inch plug of epoxy at each end.) Actually, as soon as I get done with this note, I plan to log on to www.onlinemetals.com and order my pin. I had to do a bit of research to decide which GRADE or formulation of stainless I wanted. My understanding is that the T-316 is among the most corrosion-resistant metals you can get. It costs a bit more, but at $2 a foot, I guess I can handle it. If any of you metallurgists out there want to correct me as to the best grade of stainless to use, please do! (I am only repeating what I read on a web site somewhere.) -- Steve McClellan 1981 M15 #152 Chicago Area