Add timer to Video?

Is there an easy way to super a clock/timer to a clip? I'm doing an edit for an insurance investigation. We need to show how long it takes for a vehicle to get from point A to point B.

Client would like the clcok to start at 0 at point A then stop at point B. Need to repeat this for six variations. A time code window is not ideal becaus the starting point for each event is slightly different.

I need at least 10th if not 100th of seconds to display. If it were just seconds I would consider laying in text graphics....