For cruising it is usually a mistake to save a little
money by using time-consuming systems, even simple ones like dipsticks. I simply can't imagine the nuisance of going below (in a seaway?) to check
fuel levels with a dipstick.
The problem was
solved decades ago: take a look at the Hart Tank
Tender (
tanktender.com - Home). They have 5 and 10 tank
panels. I have been using mine since 1980 with no problems whatsoever - a remarkably reliable product. Given how simple it is it does seem a bit pricey, but the results say otherwise. I would do it again in a heartbeat.
Greg