We use the DiveNDog telescoping platform swim ladder. I think ours is five step but can't recall for certain; the swim platform is about four inches under water when deployed. We have it bolted atop the cap rail just enough aft of the entrance gate that it isn't likely to get snagged when docking. I added a teak pad under the forward foot so it would be level, as the cap rail curves up at that point. We added a Starboard piece to the bottom of the cap rail that braces the tubes when deployed; gives it more stability, although it still flexes a little when boarding. This has worked out very well for us for many years. I tie it to the rail when folded up with a slip knot and dangle the cord end overboard, so if someone falls overboard when the ladder is up, they just pull the cord and it falls down.

I'll see if I have pictures somewhere.

Charlie
s/v Kamaloha
1987 T37 #542