Pics may help, but the factory shifters (Hurst or standard) lack threads on the shaft.
You'll have to cut threads on the shaft if you want to use a threaded shift knob. There's a DIY out there that shows this with pics. Do a search and you'll find it.
Edit: did if for you:
http://www.camaro5.com/forums/showth...t+knob+threads
Good luck.