Low Millage 78?
If I remember correctly when the trip reset is pushed on this style speedo, it will rotate all four positions completely until they return to zero. But if the button is only pushed partially and released it can stop on other numbers without zeroing.
I think anyone here with a '78-'82 can probably confirm this. Either way, the seller of this '78 should have caught that and zero'd the trip odometer before posting the picture.
Cheers, Greg











