J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Adding a temp gauge - 2GMF with B-panel

The 3/8-19 does sound pretty funny, but that translates into roughly M9 X 1.25. VDO should have an equivalency chart on their website....well maybe. If that's a tapered pipe thread it could be M10 X 1.25, too.