Cal 20 Transom Reinforcement

[Cal201587]

Hi All,

I've got a 1970 Cal 20. Doing some maintenance we discovered some rot in a plywood panel on the inside of the transom. The panel is cut to the shape of the transom. Is this standard on this boat, or perhaps a mod by one of the previous owners? The motor well is glassed in and the outboard bracket is on the transom which leads me to believe the panel may have been placed there for reinforcement. Any input is welcome!