Your speedo has cleaned up really well
I'm still amazed at how those rubber covers degraded. I did some searching and it seems rubber, like old rubber bands, they can either stiffen and degrade into powder, or depending on what the rubber constitution is, can turn into a sticky mess. What did you use to clean all of the old residue off?
You've had the car for 20 years, but not used for many years, so you know the history. What were the conditions the car was stored in, i assume it wasn't directly in the sun, but was it in extreme heat?