Here are the majority of the patterns I have on hand for the MK/FN/M98. I don't cut for the cross pin release and I also do not cut for the side safety.
This is what I call an old classic.
While this is more a new classic.
This is the upgraded MKX Cavalier factory.
The MKX Whitworth.
A couple older FN styles along with a semi I've never got around to building.
I also have a factory Mini MKX.
As to using a stock for a pattern. The recoil pad must be removed so a block can be screwed on. Two holes will be drilled in the front of the barrel channel to hold the from pivot. This will keep the cutter from cutting the front 2" or so of barrel channel.
The guides are an epoxy cast of the exact cut made by the router bit. Most of the outside is cut with a larger round nose bit. While I would love to say there is no chance of a mark on the pattern I can't. If someone plans on using a stock again I will do my best to not mark it. Taking extra steps like a layer of tape, running with minimum down pressure etc.