w123 voltage regulator screws
 

My lights were flickering at idle so I thought I'd try replacing the voltage regulator. I found only one screw holding it on! It was a little bit cocked in the opening.

I tried to fasten it back up in order to get another screw and the OEM part won't tighten on the first few threads. Anybody know what pitch and type this screw is? I figure if I get a pair of screws that are slightly longer, all will be right.

I picked some up from Grainger. For future reference I used M4x.70X20. I'll shim them with extra washers so they don't short out inside the alternator.