I really love the look of these old boats and yours is looking great. The bright yellow and absence of spiders is very cheerful.
It sounds like you had a stroke of luck in repowering. Up were I live (in the frozen North) I see a lot of boats for sale like the one you passed on where the owner is really selling the trailer with the condition that the boat goes with it. In fact as I recall I found my Seafari as more of an advertisement for the trailer. That guy only bought it for the outboard in the first place.