sure...
option #1: if it's ODOL, then you can easily replace the texture path with a hex-editor, no matter how long the new path is.
if it's MLOD, then the new texture path must have the same length as the original when you hex-edit it. otherwise the whole model gets messed up.
option #2: use one of the texture-swap tools. search ofp.info or the editors' depot here. you'll find about 5 or 6 different ones. don't ask me how they work in detail, i've never used one of them.
option #3: use o². select the whole model, go to the face properties dialog, select three or more faces with the same texture and click on 'filter by' on the right. (NB: the change will be displayed not until you open the face dialog anew). then type in the path to your replacement texture.
repeat this for all textures. done.
//edit.. oops, planck's quicker again