u have to take the whole unit out from the dash, well i did nayway, once u got all the front of the dash off ther are two screws holding the cluster in...
once u have undone them u can pull unit forward, unclip the speedo cable from back of unit, tight access, then at bottom of cluster will be one or two connections to unclip, depending on what fuse box u have....accss is easier if u drop the tray off from below the steering wheel...
that should all be disconnected now so pull clusterout, turn it over and on the back u will see 3(i think) screw in ights, simply unscrew and replace