well if you mean how do u get the model to work, yes you must replace it...I'm not sure if this is what you are asking..but to get teh model to work..First find out what character teh model replaces. Take Vegetto for example : he reaplces goku. There are 2 different files, a reg file, and a ssj file... Take the reg (form) and rename is to the name of the character you are replacing..for the Vegetto example Rename the Vegetto.mdl, to goku.mdl.. then for the ssj (form) take the SSJVegetto.mdl file and rename is to ssjgoku.mdl (of course you would put it in the ssjgoku folder...) I hope this is what you were looking for. If you need further help contact me on AIM
EDIT: lmao i'm pretty sure thats not what you need, BUT i felt like typing so..yea.