[alfa] help fixing late 3 series spider speedo

["Dan Hagrman" <dan@xxxxxxxx>]

Hi all,
I'm looking for any wisdom before I dig into my speedo.  It "works" but registers ~20 mph at 65mph, ~28 mph at ~90 mph.  I've checked and cleaned the tranny cable, looks & turns fine.  The fact that the odo appears accurate tells me this problem is in the gauge itself, right?  Does anyone have a spare instrument cluster they would be willing to sell or loan to me?  (working or non-working speedo, I will pay fair price)  Anyone know offhand what the cable rotation speed is relative to axles? 
thanks in advance for any help.  I've put off fixing this thing too long, and/or fixed everything else, so it's time to tackle it.  I'd rather figure it out than ship it somewhere.
dan in kc, 89 spider, home of the now complete perpetual engine rebuild

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