Switching copies

for all you guys that play with copies of MTW ,you
know one modded one for internet ,
Whats the easiest way to switch bewteen.
you know ,just tell me what you do to play both while not
having to reinstall all the time

thanks

make a seccond folder of the original, and one of the modded game

need about 2gigs

oh wait i get it you just use the in folder exe