Tried to modify text and nothing changed. Those of you who've successfully made changes -- what entries in the mis file make the plane types change?
196608,10,1,0,53,0.000000,0.000000,0.000000,78774.522643,0.000000,-68214.061304,3,0.000000
If you change the 53 to something else you get a different aircraft. Fiddle at will