Not my photos.

They are from this discussion at the Double Gun BBS

https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=117029

Note the modified sear engagement.
That's the "only way" to do this, in my opinion.
Going with the standard flat sear engagement allows the cocking piece to move side to side at engagement, leaving you with excessive windage error.