Yep, lights out first, unscrew all the fixings on the instrument panel and the left hand panel with the switches, remove the gauge surround first, you'll have to jiggle the l/h panel around a bit hence the removal of the fixings
then take the screws out holding the instrument cluster in, pull it forward a couple of inches and pull the speedo cable off, followed by the wiring loom that you can now see clearly
I still reckon you've got the wrong switch for your wipers Chuck
Are you certain you have a 2 speed motor?