You'd have to find out where they go.. trace them out. Many times you'll find they go nowhere or do nothing. Usually reserved means they are for a future revision board if needed, or they were a spare position and just an unused portion of the design. But on some rare occasions, you'll find that they perform a hidden function (debug related, hidden feature, etc). You can look at similar model boards that share the same/similar PCB design to see if that gives you any clues.

Through alternate documentation I discovered one of them inserts an I/O Delay.

At the same time I found conflicting information for two of the switches. One manual says set them to 0,0 for 64K cache or 1,1 for 256K cache. Another manual says 0,0 for 64K or 256K cache.

Might depend on the board revision. Check what hardware revision the manual is for, versus what the motherboard hardware revision is.

The manual that came with the computer, while comprehensive, doesn't refer to any revision number. And neither do any notes or configuration guide/pages on the internet. Looking at similar boards in the same family doesn't yield anything either.