86 ss with the L69 305 V8 4bll carb
have put the dash all back together after six months. only work on the car when time and money alow me to.
took it for a drive and code 24 set and speedo needle does not move.
have read about where the vss is located on the back of the speedo so I might be able to check it.
I have pulled the speedo back out and din't see the vss on the back of it. thinking I might have left it off I looked under the dash but have not found it.
is there any place else on the car it might be installed ?
I do not want to pull the dash off again...

Under the dash, near the steering column will be a small, green box. There should be 2 or 3 (can't remember) wires coming off of it heading up in the direction of the speedo. On the end of the wiring is a black plastic optic eye. That is your VSS. it bolts to the back of the speedo & is for the purpose of sending a speed signal to the ECM & cruise, if your car has it. It does NOT control the speedo inself, our cars use a cable driven unit. If the speedo itself is not working correctly, the VSS won't get a reading & therefore show a code 24. Find out what the issue with the speedo not reading is, & the code shoudl go away.

thanks I will look into it.

Yep, he covered it all.

there is a small wire that has a small screw in it that holds the VSS optical reader on the speedo head, is it there? Is the cable hooked up on each end?

Thanks for all of your advise.
I found the vss hiding behind all of the radio wires, must have forgotten what it was for after six months.
reinstalled it and it works!
just have to get the speed needle put back on just right to read the correct speed.