The case, if it isn’t broken anywhere, and is in really good condition, will have more collector interest, and as much, if not more value, than the motor. The difference isn’t in the motors, its in the oil. Manufactures were getting away from running SAE 30 wt, 4 cycle, crankcase oil, and recommending that TC-W be used instead. Even in there early motors. I have a 1960 and a 1961 that I run 3 oz of oil per gal. in. Ive had the 61 less than 20 years. The 1960 Ive had for over 45. Here is a link to them. https://youtu.be/r1vVMls8OU4?si=NdmAEKDiDNqX7EW- Not a recommendation, Just what I do.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.