Need Help Badly!!!!!

I want to help but all I can offer is how I do it. First I must point out that the factory did make the harness branches long enough to be servicable. I.ve never fecked with those main harness clips to pull the inst. panel.
Now If the car is colum shift automatic, set the park brake as lowring the colum will take it out of park. I pull those down into drive anyway to get shift lever out of my way.
I wont fight the connecter on the headlight switch either. One screw holds the fuse box, take it out to access the release button on that switch and remove switch stem/knob. Screw off the switch nut and remove from panel. I put all the switch pieces back together and leave it lay there in the dash housing.
Pull out on this side of inst. panel and you should be able to see the speedo cable. Grab that cable housing and pull it toward the panel. It will almost push the panel out of dash and give you the slack you' will appreciate when reconnecting.
The retainer on the speedo cable is similar to hallf of a clothes pin Wrap and hand around cable and it , squeeze and pull away from panel.
Sure hope this helps.