Are you still looking for new Tachs? I just replaced my Stewart Wagner (SW) tachs with ISSPRO programmable ones. I could not find a tach that was compatible with the SW signal generator. I have two tachs and signal generators that still work if you are interested in purchasing them. My tachs on the fly bridge were not working so I ended up replacing all 4 along with the two engine signal generators. The lower helm tachs and generators were working fine.