I think it's the other way around. You'll have to buy a rally set with the speedometer, then swap you KM speedo unit in place. Reason is you'll need the housing and printed circuit that belong to the Rally Gauge set.
I checked the parts book for 69, and the speedo head is the same for both standard pod and Rally gauge set.In the right side opening, you can install either a clock or a tachometer. These are separate from the speedo/gauge cluster. Or you can leave the blank plate there.
Glenn Uettwiller
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