If the target is a down rigger mount, I had some brackets made up for my previous boat that worked great (see pic). Before these I was using Scotty #1015 side mount brackets.
My hull was also at an angle. if you look closely at the pic you will see a black shim. I cut that at the correct angle on a tablesaw from a piece of starboard I had around. The aluminum brackets were made by "Fish On Fabricators" based in Alabama. I sent them a drawing of the shape with measurements. These guys were terrific to work with. I was happy with the pricing even with the mail cost. That was pre-covid. Anyway, I mention them in case you don't have a local fabricator.
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