Yes, SWA is now a "participating" airline in the Resort Airline Check-in service at most WDW resorts, including the GF.
We have not used it with SWA at the GF, but did at the BC in March and it worked great.
There will be an RAC desk near the main entrance of the GF--either inside or outside--where you will need to take your bags to check them. You can check bags and get your boarding passes as early as 12 hours before your flight, but have to have the process completed no later than three hours before your flight.
If you used DME on the way in to WDW and have a morning flight, you may get your BPs and temporary bag tags delivered to your room the night before. You still need to take your bags to the desk and go through the process, however.
RAC also supposedly is doing check ins at or shortly after the 24-hour mark to get boarding numbers for SWA passengers that used DME on the way in. However, they aren't actively advertising this aspect of the service and I haven't seen enough evidence that this is working well enough that I would rely on it for my boarding number assignments. If you have paid for EBCI, you still will get checked in at the 36-hour mark and RAC will just print the passes with those numbers. Otherwise, I'd do the 24-hour check in myself. If RAC beats you to it, no problem.
