I have a three handle diverter that i need to remove. i removed the handle. and then the brass nut that i thought would be the final step, but to no avail... the problem lies with the shaft of the diverter because it is plastic. i have a screw from the handle to thread into it. if that is any help. the base of the diverter is brass and i do not see another nut or anything to grab a bight. any thought????????