Anyone know how to calibrate the water temp reading on my 08 24 SSV?

[tg0824SSVGG]

Hey all,

Ever since I got the boat, the temp gauge reads 3-5 degrees higher than what the water
really is, and while MATH is simple to figure out the real temp, does anyone know how
to calibrate what the thermometer reads?

There are all kinds of calibrations for the speedo, etc - but I haven't figure this one out.

Any ideas?

08 24 SSV Gravity Games

[tg0824SSVGG]

Never got any responses, trying again...