shoe for the 39-453 model

Hello,

To detach the 39-453 arm attachments, you can start by looking for a cut-out in the sash track that you could slide the shoe out of. If there isn't a cutout, you could possibly slide the shoe out of the end of the track. Once the arms are detached from the window sash, you'll need to remove the installation screws from the base and slide the entire assembly inside through the cutout in the sill trim. Thank you. 

I believe that you will need to remove the track to release the operator's shoes from the window. Normally the track is in two sections. If you unscrew just one of the tracks you should be able to slide out both pivot shoes.