My Plan was to drill 1" pilots in 3/4" plywood - attach that jig to the outside toe rail with the original hole on the bottom of the hole in the jig and drill it that way. I have to go to the boat to measure exactly how wide the toe rail is - all 1" or 7/8" carbide hole saws may be too shallow to go trough in one step.
I think I found the right hole saw for this job - https://www.homedepot.com/p/DIABLO-1-in-Carbide-Hole-Saw-with-2-3-8-in-Cutting-Depth-DHS1000CT/301697676
I think I found the right hole saw for this job - https://www.homedepot.com/p/DIABLO-1-in-Carbide-Hole-Saw-with-2-3-8-in-Cutting-Depth-DHS1000CT/301697676