An OMC manual for a 1977 35hp Johnson motor appeared on eBay today. Even though mine's an Evinrude(same hp and year), I believe it's the same for this model and year. In trying to determine what I'd be willing to pay, I consulted the Ken Cook site. I noticed that the Evinrude service manuals were $40 but the Johnson manuals were only $20, for 1977. Aren't they both virtually the same?