Ok, found my notes (I really should put this wiki back up...).
Could it be RFKILL that disables it? In my case, it's controllable with `AT+CFUN` http://natisbad.org/E4300/Dell_Wireless_5530_AT_cmd_ref.html#ATplusCFUN though I still have at least one `ttyACM0`.
``` AT+CFUN=1
OK
AT*E2GPSCTL=1,1,1
OK
AT*E2GPSNPD
OK
```
I also have mentions of ModemManager and `mmcli`.
I did have a patched version of `mbm-gpsd` packaged for ArchLinux for a while https://aur.archlinux.org/packages/mbm-gpsd-pl4nkton-git. I still have it installed actually, but haven't used it or a while.