Actually Rich, droop and downstops have incorrectly become synonymous in a lot of racer's vocabularies and I am just as guilty as the next guy. I know what you mean but the others may not.
Downstop==Point measured (in millimeters) at lowest part of arm or knuckle relative to the chassis, with the chassis being 0mm. This is typically measured with the chassis on blocks and a stepped gauge.
Droop or Up travel (what Empire team uses)==Car settled on flat board ready to race. Hold a metric ruler perpendicular to the flat board and slowly lift the chassis. Note the measurement from the settled ride height to the point where the tires lift off the board and this is your actual droop or up travel measurement.
That said, am I to understand you have the rear downstop screws backed out entirely? I can just see Ron watching this thread now laughing his ass off