I recently bought an older (25+years?), Honda 2hp that seems to run ok, but after leaving it with a shade tree mechanic who cleaned the carb - I got it back and discovered that the sight glass over the oil level window is missing! Of course he denies knowing anything about it, so ok, how do I get & install a new one? This outboard is identical to the one that I purchased new in 1992 and used on my dinghy for 7 troublefree years on Cape Cod! Thanks!