If you have GTA SA Ultimate Editor go to Animation and select rifle for the three lines, and other way is opening weapon.dat and change buddy to rifle and its ready about the RLauncher is hard to make shoot in 3rd person lol.
Man, you did a nice job . BTW, i guess that the rocket launcher aiming could be changed in weapon.dat too. I tried it on Vice City once, the M4 didn┤t appeared to be working, then i changed the controls to classic, and it was aiming like other weapons (wtf! ) but just when i clicked to shoot, game crashed xD. Lesson: Never change codes unless you know what ya doing p" />