Hi Brent,
The odometer on my TR4 died many years ago. The speedo continued to work fine. Your mechanic is right, it's most likely hooked up fine, or the speedo wouldn't be working. However, you can most likely have the gauge repaired and it might be worth rebuilding the whole thing at one time rather than just fixing the odo.
If you have a lot of speedometer error due to a change in the gearing in the differential or tire sizes different than the originals, it would be possible to correct that, too, while it's apart, if you wished.
I haven't really looked into getting mine fixed yet, so can't recommend anyone in particular, and I don't know the prices you might expect. But, there are a couple places that repair TR speedos (check the archives here or Google on the Internet, or perhaps some other BCF members can make a suggestion). Also, I've heard, but can't confirm, that repairing the speedo or modifying it for diffeent gear ratios/tire sizes isn't all that difficult a do-it-yourself job, if you feel up to it. There have been a couple previous posts about this and ISTR seeing a resource on the Internet with a lot of detail.
Hope this helps!
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