usually if you buy a jet boat pan they will fit a jet boat! there really isnt a general number to go by, but truck pans will sometimes fit! some motors sit higher then others....
a good for instance! my buddy bought a mach 1 jet boat minus motor....a couple days later he buys a seguaro jet boat for the healthy BBC thats in it...so we pull the healthy BBC out of the seguaro "deeper entry" boat, and go to drop it in the mach1...mach 1 "low freeboard" boat...the healthy bbc had the truck pan on it, and we go to set it in, and it is resting on the intake with about 1/2 an inch to hit the rails on the rail kit...so we pull it back out, and put the 10qt jet pan on and whalah...it fits
im just saying its not always the circumstance