3.0 Milano speedometer problems

["Gene Fine" <emfine@domain.elided>]

I have a 1988 3.0 Milano, and the speedometer is inaccurate to say the
least.  When idling, the speedo reads 10mph, when doing about 65mph, the
speedo reads 40mph, and when passing every other car on the interstate like
they are standing still, it reads 60mph, and won't budge past there.
Naturally, I'd like to know how fast I am really traveling.  I figure the
problem is either the sender is toast, or the speedo is toast.  Has anyone
else had similar problems with their Milano, and could you suggest which one
to test first?

Thank you,
Gene Fine
Cincinnati, Ohio
67 Giulia Sprint GT
88 Milano Verde 3.0

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