First thing would be check under seats and in glove box for key for the lock nuts.
If no go. You should still be able to get axle shafts out. Open diff cover, remove pin (and small bolt that holds pin in). Disconnect caliper bracket from anti-moan bracket. This should let you push wheel and axle in enough to pull C-clips and then remove axle. Once axles out, even with wheels still on, go to yard office and see if they have key or can cut off back of stud that lock nut is on. Once cut flush to back of flange should be able to hammer/punch stud out toward wheel. Wheel should come off now. You may need to replace a stud or two, but they are cheap.