My 1983 Bonneville speedometer has been jumping around ever since I rebuilt the manual transmission. Prior to that I had no speedometer for many years because the cable had touched the exhaust pipe, melted, seized, and broke the drive gear loose from the output shaft. So I had to take the entire transmission apart to secure the drive gear back in place. Since the car got a brand new speedo cable I was puzzled as to why the speedo was bouncing around so much. Today I put the car up and took the cable back out. It was fine, no rust, no kinks, and I cleaned and lubed it anyway. When I tried to get the cable back through the firewall and up to the dash I was confounded by all the junk in the way. That is when I realized that the convoluted path the cable must take is probably why the speedo is bouncing. When it was an automatic car I guess the cable path is less crazy. But now with the new clutch linkage directly in the way I can't even get the cable past the pedals. Worse, the Pontiac dash has a triangular shaped tunnel that the cable must pass through that goes through the ductwork and exits nowhere near the firewall hole. I need to make a new hole that is a straight shot to that cable tunnel in the dash. I fed a long rod through the tunnel to see where it ended up. It passed close to the neutral start switch on the clutch pedal and hit the firewall at a fairly empty spot. It got dark so I quit but I think the power booster may be in the way on the other side. Has anyone found a better place for the cable to pass through the firewall?