Mine were not in really bad shape but I removed and refinished them. I sanded down (but not completely to bare wood) and used regular amber Captain's varnish which takes many coats for good coverage/durability. However, the next time I do them I will use water-based HALCYON amber gloss varnish that I have used on my hatch boards and some interior cabinets refinishing
https://www.totalboat.com/products/halcyon-water-based-varnish
The halcyon is very easy to use (much easier than conventional varnish that didn't work better in my experience), does a great job and is very durable.
One tip .... as part of my final coats, I mixed a small amount of grit (I think fine silica) into the varnish that I applied with a foam roller onto the front edge of each step (about the front 1/3). It didn't affect the look but added a very nice/functional anti-slip edge to the front of the steps to help avoid falls.
Dave Hupe
1994 C320 #32
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