I have a new 1960s road worn strat and the whammy bar that came with it has no thread so it doesn't screw into the bridge... I have other whammy bars but for some reason they all won't fit the trem block.. is there anything special about the 1960s road worn trem block or the whammy bar? Anyone know? Thanks

I'm not totally understanding this. Is the guitar new? If so file a claim. You said the trem bar has no threads. Is it made without threads or are they worn off? If it's made without threads the the trem block isn't going to be threaded either. Is there a screw hole in the bottom of the trem bar? As for the various sizes, yes, it's not uncommon for different guitars to use different trem bars. I had to buy a bar for my Clapton Strat and couldn't use one off the wall. Had to order it. I don't know about your particular guitar but it wouldn't surprise me if it uses a specific bar. And why guitar companies can't make things like that more standardized is beyond me.
MULLY
greedy I guess