Could be, but that would be a pretty bad error. For example, he's either going 69 when the speedometer reads 60 or he's going 60 when the speedo reads 69. Either way, pretty bad, and across the board it's a 13 to 15% error.
I would have to think the top numbers are the indicated speed and the bottom numbers are actual. Maybe they swapped in a taller rear gear ratio and couldn't figure out how to swap the speedo gear?
I like it - really displays the Brougham era to a tee. Start me off with a complimentary tank of gas, and I'll catch you in Vegas in 8 1/2 hours.
Yes, because he could have any number of problems; Babe has a low-speed error from a broken driven gear tooth, but I haven't prioritized getting a new gear for her.