Does anyone know the correct Trico prefix for 16 inch wiper arm inserts. It would be like PR-16 or PL-16 or the like etc. I have a thick "Parts and illustration book" that lists parts by group number and the part number. The GM part number for the 15 7/8" trico blades was 14029850 but no help with the Trico number that you would find on their packaging.