The bolt is from one of the Romanian parts kits I bought. The pins just pushed out by hand when I took it apart.
The boring tool is a ground-down 1/2" end mill. I made the toolpost years ago; it has a slot for a 3/8" tool at the correct height, and a 1/2" hole for a boring bar on center.
The metal cut easily enough, and the sharp cutter didn't care about the interrupted cut. The Romanians put a great big dirt groove around the perimeter of the bolt face, which makes it look funny when the OD is opened up. I'm not sure what it will do to the soft shotgun shells when fired, but from comments on Saiga-12.com some Saigas are like that and it doesn't hurt anything.
I haven't recut the extractor yet. It sits at an angle, and the rim on the shotgun shell is round and not as tall as a 7.62x39, so I want to grok it in fullness before cutting.
I managed to salvage the mis-bent Tapco flat. I adjusted the hole positions with a diamond bit, then cut off the screws to the right length. I have a piece of 3/16" steel flat with a 10-32 hole in it. If you grind the screws down until they're just proud of the opposite side, they're correct for the front trunnion. This flat is sacrificial, since I wanted to figure out the magwell mods on a $15 Tapco flat instead of my expensive AK-Builder underfolder flat.