[AL in NY]

One of our older club members has one of those spring loaded toe-in gauge tools that has the small chains at each of the pointed ends. I don't know the manufacturer's name or model number. I am looking to find an instruction sheet for the use of this tool. Several other club members have tried to use this tool and they can't get repeatable readings with it. I tried the tool on my 30 CCPU which has had the front suspension and steering serviced and my readings are very repeatable. There seems to be a problem with the procedure and how to get the correct reading. Can anyone help clear this up????