Verified answer

The speedometer cable on a 1970 Beetle runs from the speedometer to the left front wheel. It goes through the spindle and fits into a square hole in the wheel bearing cap. There is usually only one problem. It probably broke. All you do is disconnect the speedometer cable from the back of the speedometer, yank the cable out with needle nose pliers, pull off the wheel bearing cap, pull that end of the cable out, grease up a new one, slide it in from the speedometer end, fit it in the speedometer, and put the wheel bearing cap back on. If you can do it on your ten speed bike, you can do it on your Beetle.

Vw Speedometer

Your speedometer cable goes from the guage to the transaxle. It runs the full length of the car right down the middle. they are also notorious for going bad.