You could but you really don't need to. As long as you check in at T24 (or as close as possible) you can just print your boarding pass when you get to the airport. It doesn't matter when you actually print out the pass as long as you have it before you enter the security check point. The closer to T24 the lower boarding number you will have.
For the trip home you could;
Pay $10 each and have southwest check in for you at 36 hours instead of the usual 24 hours (Early Bird Check In). This is what I always do on the way home for the convenience.
Have a trusted friend or family member check you in from home at T24- just give them your confirmation number.
Guest relations at any of the WDW parks and resorts will also check you in at T24 and print out the BP for you.
Again, you don't need a printed BP until you get to the aiport as long as you have checked in and secured your boarding position. You will get your boarding pass for all legs of your tip when you check in at the airport.
Southwest has a nice video on the website about the boarding process - I think it is called boarding school.