Speedometer Advice Needed

[Tony Smith]

Originally posted by Bob Moseley
The other mystery at this stage is what does the number on the circular plate on the rear of the speedometer denote. We are led to believe the number 5 on the 2pdr speedometer was specific to the speedometer gearing. Is this the case?

Bob

As all of the gauges pictured have had different numbers stamped, and it is my certain belief that all the speedos have the same "indication to cable turns" ratio (even the 100mph speedo), I would suggest that these numbers are a quality control inspector's stamp after the unit has been calibrated or inspected.
Here is a S-W Jeep GPW gauge, model 590 AB L1 (dated Jan 43). Note that it has 2 stamps on the centre cover, 07 and 20. This site has some info on S-W gauges in Jeeps, and confirms the same dating codes used by Stewart Warner.