how do i install cars with out wadinstaller

i have got most of the F1 2004 cars but not renault & sauber, i have got 4 cars with wadinstalled and 3 of them install Ferrari, mclearn and toyota i have the jaguar but it has wadinstaller but it has 3 version and none of them install but my main problem is how do i install cars that use easywad i have done wat it says in the read me files and i unpacked the cars.wad then but the files in then packed it back up can someone plz help me coz i love this so much coz i have had it a year and been unable to play but now i got a new computer it works and i just need to know hoe to install the cars that use easywad

thanks
jay