If it's just a few 10's of rpm you will see an adjustment screw on the governor cam, disconnect the cable, set the rpm and the re attach the cable, adjusting it accordingly. If it's a bit more than a few 10's of rpm, best get Finnings in as there is a second screw that has to be backed out in the governor to accurately set it. I have the CAT instructions at the boat, off there tomorrow, drop me a pm before Sunday and I will take a shot and send it to you ( that's for the simple adjustment)