the best way to figure this is measure down from your trailer bunks
to the lowest point fin or drive shaft that will cross you horizontal section of your lift. also take into account if you have your lift tilted back slightly or level. i have been about 8 inches lower in the back to accomodate
our low water levels when they drop our levels. my shorestation bunks
are about 3/4 of an inch to low for my fins to clear if they drop our water levels we are kind of the red headed step children on the lower river here.

Chris