1 year and 7 months later...
Well, I ended up sending the gauge cluster back to the speedo resto guy. He said the speedo head was too far gone to make it accurate. So, I bought a so-called "refurbished" unit on ebay. Ha! What a crock. I had the thing in and out four times yesterday. The oil gauge pointer was stuck to the face. Then the oil, fuel, and temperature went full scale. I swapped out the cluster voltage regulator. Then the fuel gauge kept sweeping from half full to full and back. I swapped out the fuel gauge. Now with all that working, the speedo is acting goofy. A 20 mph, it registers 15 mph, at 70 mph it registers correctly.
Any ideas?
Oh and this gauge cluster was advertised with a really cool looking white face. I've seen that done really nicely before, however this one came with a really cheesy looking white decal with the MPH numbers that has been applied to the face of the speedometer. I guess "buyer beware" is what I'm trying to say.%)