My Powermatic 3520B (and Jet 1642) are lacking when it comes to locking or indexing the headstock. I don’t do indexed work, but do want to lock the headstock.  Usually, I want this when I’m sanding a section or otherwise want the piece held still while I work.

The provided option is a set screw that you have to wind into the indexing holes. Probably good for holding the shaft in place, but not easy to lock and unlock.

So I took an old drill bit of appropriate size and epoxied it into a handle I had laying around.

I tapered the end slightly, and now it fits into the indexing holes.  And I can lock the headstock in place quickly and easily.