Just purchased a boat . it has a tach in console but not hooked up. I am not sure who mfg the tach. the emblem is 2 vertical lines with a T in between them. I have a mercury 4 cyl 40 Hp engine and not sure where to set the pole switch on back. it has 4,8,10 and 12 pole. If I can figure out who made it I will contact them. Thanks for any help