Speedo/Odo/Fuel range

[Dave Shreeve <shreevda@cannondale.com>]

Hello all-

I have recently acquired an '88 5kcstqw with only 61k+ registered miles
- that's when the speedo/odo quit working.  [The previous (one and only)
owner estimates that was about 40k miles ago.]

Could any of you help me guess where to best start toward the solution?

Could be remote sender or head unit.  Haven't had the chance to start
diagnosing.  Interestingly, the computer fuel range still functions, and
seems to be fairly acurate.  From where is the mileage data for this
obtained?  Rest of computer functions (except pressure gauge) are dead.

Thanks in advance for your help!
-David in CT