I replaced the original traveller on my O’Day 28 with one from Lewmar. That particular traveller has a slot on the bottom where the bolts slide in and use the same holes as the original traveller. I had no trouble accessing all the bolts but for reasons I can’t remember there were a couple of holes I didn’t use. I just filled those holes with 3M 5200. One of the best things I’ve done to the boat. Yes the nuts are accessible inside the electrical panel.
