Super simple, 3 part, plus stepper motor with lead screw. Could have done in 2 parts but slider in 2 parts makes for easier control of close fit on frame. Use short 1/2" long #4 & #6 wood or sheet metal screws.

Motor:
https://www.amazon.com/dp/B01LNJFKA6/?coliid=INZTVAXM4EFI4&colid=2SQKPSVXB57SY&psc=1&ref_=lv_ov_lig_dp_it