Quoted From 3SheetsDiesel:
Welding a wrench to the drain plug will make it worse, since you won’t be able to turn the plug enough times to get it out of the pan before the wrench runs into something. If memory serves, the drain plug is a 13mm.
I’ve got a 1996 Neon and I’ve always used the 1/2 inch 6 pt on it. 13 mm is close it may also work which ever has the least play.