adding a water pressure gauge

I don't have a water pressure gauge on my boat. I would like to add one as I plan on adding a jackplate in the future. How easy is this to do? My dash has hole with a plastic plug that appears to be for an additional gauge. The motor is a 2002 yammie 130 2 stroke on a 2002 ranger 175vs. thanks for any info or tips and tricks.

there should be a nipple or plug on your block. i believe you just run some speedometer tubing from there to the gauge and hook it up. try to find a gauge that matches what you have.