Pic 1. The Standoff Tube (WI-103) of the left wing provided a "bow' as called for on page 2-36 of at least 3/16 inches without the need to use a washer AN960-416.
Pic 2, The Standoff Tube (WI-103) of the right wing needed 2 washers in order to provide (AN960-416) to provide the "bow' as called for on page 2-36 of at least 3/16 inches. In my kit the length of the left and right Standoff Tube wires were different. I suppose this was a manufacturing issue. .