Will the original lights from the stock indash clock work in the tic tock tachometer

 

They should. That's what I did with my '68.

Randy C.

 

67 or 68-69/ 70-72? Bulbs or bulb sockets? 67 yes to both the bulbs and the sockets. 68-72 no to both the bulbs and the sockets. The 68-72 standard clock uses a push in socket and 1/4 turn bulb. the 68-72 tach uses a push in style bulb and a special socket that is larger than the sockets in the speedometer or fuel pod. These are specific to the tach.
See pics below showing the back side of a set of 68 rally pack and you should be able to see the differences in the sockets.

 

For reference, here is the light harness from a 68-72 in dash clock (no tach).

 

If your question was: Can you plug the connector in the dash harness that would plug into the harness pictured above into the tach to power the tach lights? then the answer is yes.

 

And the diagram for the T-T-T should be in the Accessories sections at the end of the CSM.