Type of Tension Gauge

What type of tension gauge provides the proper figures for a Flying Scot? The Model A Loos Gauge (which I have used for the Catalina 22) gives one figure and the Model PT-1 (with the two rollers and the spring)gives another figure for the DORKFISH's forestay tension. Help? Yes, I am using the correct size of wire diameter for each respective gauge :) Tommy Smith DORKFISH Hull 4909