Alll the people above are correct, it will be easier that way. I'll just post the current way, in case that doesn't work for you or whatever. Extract act.img, and find the file names for the strafed you want to swap, it will be obvious. Swap the names both ways, save the act with the edited strafes and put it in game. If you swapped preppy and greaser, all greasers will have preppy strafe and vice versa.