I struggled to find reliable information on which (new) hardcases that fit my Mustang. It is a MIM Fender Mustang P/J FSR black/tort with maple neck and fretboard.
I ordered two Gator cases from Thomann, as local shops did not stock these models.
Gator GC-ELEC-XL (part number 212516). It does not fit my bass, as the bass is too long by approz 2 cm (3/4"). Also, the G tuner in "worst position" would make this even harder to fit, even if the back end foam was cut out.
Gator GW-JAG (284273). Length is perfect, with about 2 cm to spare. The case is unnecessarily wide by 1" top AND bottom, but one could add ie a strip of foam to position the bass body better, if you carry it longer distances. However, as the distance between the lid and the lower part fits perfectly for my bass, you feel the bass in a reassuring grip, once the lid is closed. No sense of the bass bumping around as you walk.
I might add pictures later.