Welcome to AAPK Scott! Very nice old display, from the looks of it and the number of Delrin handled knifes I’m guessing it’s from around 1970 +/- a few years, maybe into the 1980s. But wow, where to start!?
I’m of the “keep it as original as possible” school of thought. I like to preserve history whenever possible. First, how are the wires attached to the board? It appears to be an original factory display and if so the wires are twisted on the back, which means you can carefully untwist them, and remove the knives one at a time. Clean the knife, then use the same wire to put it back. Whatever you do is going to take time and a lot of work. Don’t get in a hurry! When cleaning knives it’s very difficult (often impossible) to correct a mistake, so unless you’re a pro, slow and steady is the rule of thumb.
All posted thus far is good advice. Here’s a compilation of threads about knife cleaning. viewtopic.php?f=37&t=54157#p600904
Recommend you take some time to read through them. Pencil “lead” (graphite) is a great tool for what it appears your knives need. If it was me I’d invest in a couple of those flat-sided carpenter’s pencils - lots more “lead” to work with so you won’t have to read-sharpen as often.
The Delrin has what’s called “Delrin haze”. That can be remedied fairly easily. viewtopic.php?f=2&t=47409&p=489100&hilit=Haze#p489100
I don’t know if your board was originally part of a free-standing or countertop display, but if you just want to hang it on a wall I’d look into a shadow box type of case to mount it in. Should have a glass, or plexiglass cover to help protect the contents. They’re expensive but you can get glass with anti-UV and non-glare coatings. Those kinds of glass and shadow boxes can be purchased at art framing stores. Most will custom build whatever you want. For a price of course. But you already have a valuable asset so why not protect it.? JMO