I have a number of Mauser trigger guards to mill. ie enlarge screw head counter bores and chop 0.150" off the top of the magazine box and action screw boss. I've come up with a complicated and time consuming set up with an angle plate, 1-2-3 blocks and cant twist clamps.

Is there an easier setup to cut down on the time and fussing around it requires? Thanks

What if you took some square steel tubing, large enough to insert the TG in the center. Then mill openings for the mag box, trigger bow, and front screw boss. Secure this fixture to the TG with a nut and bolt at the rear and clamp at front. This will give you a secure flat-bottomed fixture that will expose the top of the mag box and boss for milling. You could move and clamp it anywhere on the milling table. To open up the counterbores, flip the TG over and clamp.

Thanks Bobster. I'll draw it up and get some tubing. The magazine box will make a bunch of noise but it should be a lot faster than what I'm doing.

You might be able to fashion a wooden or poly insert to dampen the box vibration.

To cut the top of the box without a lot of chatter just use a small diameter end mill. Something like 1/2 inch dia and run the mill lengthwise on each edge. Make the edge of the mill do the cutting so the cutting force is along the length of the box edges.
I would not climb cut on the length wise edges.

Stuff something in the magazine well to kill any tendency to chatter.
You could use a piece of atuo heater hose or roll up a piece of bicycle inner tube and cram it in the magazine box.