You're right, I used to draw on velum with ink, tape a drawing to a board and use a "T" square and a few triangles, now I use a computer and
Things have changed over 35 years.
From what I can tell, the shape of this detent isn't really that complicated. A replacement part could
My only reason here was to keep from having to make and stock special parts. PTP has done that with a few things and now try and find a sear pin for their