I have a Gapco Window that is missing both channel balances. The window sash measures 20 3/8 in high by 34 in wide. I want to know what length would work. I have identified the other Gapco windows in the house as the series 351 with 19-002 top and 15-002 shoe (I think). They are stamped 2530 BSI. I attached some photos to make sure I order the right parts.
