T-Bird SC Odometer/Speedometer Gauge

I'm picking up a 90 SC tomorrow and was told by the current owner that the Odometer went out about 2K miles ago and shortly after that, the speedometer started to "Bounce Around".
He said they are electronic gauges.
So is this an EXPENSIVE FIX to have a mechanic/electrical shop do/
I'm not all that mechanically inclined.
Opinions/solutions are MORE than welcomed.

Roger