Bought a Simpson voltmeter and the 3 bolt housing is about .050" too big to fit in the dash hole. The housing is plastic so took the meter out of the housing to see if I could make it a little smaller. To my surprise the voltmeter is exactly the same size as the original voltmeter and fit into the original housing perfectly, even the screw holes lined up correctly! So if you like the looks of this gage and have an old one to rob the housing off of it will fit perfectly.
Picture with the box is the plastic housing, 2nd is new gage in the original metal housing.
