Shift knob Interchangebility

[Alvin and Lucille Johnson <johnson@ids.net>]

Like many long term auto addicts, I have a selection of shift knobs,
most with innapropriate threads. Do speed shops or hardware stores sell
threaded inserts so you can drill out the knob and pound in the proper
thread to fit? Think I remember seeing these with early Hurst shifter
sets. 
Al J.