If your wood screws turns just past the proper indexing point you can put some accrglass in the hole and stop the screw at 11 o'clock, once the epoxy hardens you can tighten it to the proper position. Another method that works well at times is to relive the counter bore in the grip cap a bit to get your proper indexing point. I just used that method to time the buttplate screws on Brent's Greener and it worked very well, a 60 degree cpounter sink is handy for such a job. As for wood screws, I make them on a lathe using coarse dies, works slick and you just index the slot as needed like on any machine screw.
