[OG68]

Most common problem is the electrical contacts become pitted and burn't over the years. The operating mechanism may need a drop or two of light machine oil.

68 and 69 clocks and tachs are easier to remove than replace. A 1/4" ratchet with a flexible wand extension works well. The hardest part is getting the screws started when installing.
Pontiac recognized this and opened up the mounting tabs on the 70-72 tachs/clocks allowing the screws to remain in place. Just loosen the screws, rotate the clock and remove

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