It might seem like daft question but how does one get to the bulbs in the speedo to change them..?

 

Speaking for the earlier cluster, through 2000, I think, you remove the speedo for access and pull out the gray "rubber" bulb sockets to get at the bulbs. The sockets are a friction fit. The later version cluster appears to have a white panel you'd have to remove for bulb access, but I've never had one in my hands.