Yes follow the manufacturers info or as above water
line computations, just be aware that Insurance company's will pretty well accept any input (even insurance survey's from non registered surveyors! in some cases) but it's a different story when/if you go to make a claim, any thing falsely reported can or will lead to possible non -payment!!
I recently had to make a report on a TOTAL loss situation where the vessels owner had submitted a insurance survey
from a so called "QUALIFIED" yachty type calling him self a surveyor(based on his experience),
bottom line the insurance company did not pay out!, be sure any survey
is conducted by an approved accepted society like IIMS or SAMS,