The Mark 20 elbow will work and swing if you file it for clearance just a little bit. On my Mark 30, I created a cross shaft using simple hand tools, that adapted the Mark 20 elbow.. No lathe or milling machine required.It worked just fine. I sold the motor; so sorry, no pictures. I think the KH7 elbow is the same as the Mark 30 but the tiller cross shaft is unique to the Mark 30.
I appreciate all the suggestions and info you’ve shared here. Have decided to keep the Mark30 as is. There are plenty of boats near me to find the unique one that will work with the basic features of the 30. Sitting in the barn didn’t do the rubber hoses any good. I’ve got my must have parts list completed. Fortunately the barn it was in had a concrete floor and insulation and heat that helped protect some of it. No critter or bug nests to deal with. A little cleaning will make it look much better. This is my winter project so no rush to get it going as the garage is heated. Thanks much for your help.
Thanks to all the suppliers who sell old Mercury parts. I’m able to get the parts needed to get it running for under $200. I appreciate all the vendors who have helped me get this far. Now if I could do as well with auto repairs.
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