Alan, I think that a stock 30H is just as "valuable" as a Mod-motor 30H. It really boils down to what you want. I started doing race motors because very few of them remained strictly stock for very long. I didn't want to be bothered with "perfect" paint and paint colors,for example. The mod motors have a macho appeal but are rather impractical if you plan on running the outfit. Society today just doesn't have any tolerance to the noise of someone else having fun. I like to modify various aspects (ignition, exhaust, carbs, etc...) of my restored motors yet spend a lot of time to make them totally functional as well as look good. The gearcases on the older Mercs are the high priced item to find and to make/keep functional. I have several stock Mercury's with minor exceptions to color, decals, and paint. (20H, 30H, 55H, Mk55E, 2-Mk75's). I must admit I am partial to the Mod motors as it allows me to modify them the way I want to and many of the modifications may include very rare parts, or parts that you make.
It sounds to me that you have a boat and motor that is certainly worth your time and money to restore. The fabric deck isn't that big a deal. Go down to a local private airport (glider club etc.) and you will find all the help and advice you need. Good luck & enjoy!
