from your sig, it's an 87-93 right?
1) remove the switches by gently pressing the tabs (they are behind the switch levers) press those tabs and pull out the entire switch. Remove the wire connectors on the switches obviously... be gentle on the tabs, they break easy but it's not a "huge" deal if one of them breaks.
2) remove steering column plastic by remove the 3 phillips head screws (under)
3) remove the panel below the column (flat plastic piece)
4) remove the bottom screws or bolts holding the cluster bezel, should be 3 (if I remember)
5) remove the two bolts on top of the cluster bezel, I think the size is 9/32...
6) remove the bezel towards the steering, then pull up (it can be removed, just angle it until it clears the steering column
7) remove all the screws holding the cluster to the dash
8) gently pull the cluster towards you, detach the two harnesses (one of each side), the connectors will need to be pressed on each side to free it.
9) the speedo cable has a white plastic piece, press it and it will free the cable.
--- as far as I can remember --