Answer:
Gb Scale: Gb, Ab, Bb, B, Db, Eb, F, Gb
Positions Starting at Low Gb: 5, 3, 1, 7, 5, 3, *1/6, 5
Positions Starting at Higher Gb: 5, 3/7, 1/5, 4/7, 2/5, 3/6, *2/5/7, 3/5/7
* The first numbers are the most commonly used.
* The higher notes like from E and up have a lot of alternate positions and some positions depend on the instrument and the tuning. Some position charts say like 3rd position sharp and others just say 3rd position. The positions i put up there are close to where you should put put your slide.