[ERA Chas]

I set the height as measured at the flat of the lower edge of the frame, measured right in front of the brake box and at the aft edge, before the rear kick-up. I set mine at 4 7/8, F & R and I think the manual wants 5". Remember, the wider rear tires add rake by their larger diameters.
Try 5" as a baseline and readjust to taste. The lower the better.