If you switch the wires on the terminals it could very well finish off the gauge. That would essentially connect 12 volt power to the sending unit side of the gauge which is usually not good. Also, be wary of aftermarket sending units, some work, many do not.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine