This may help you too, it's the Army Technical Manual for armorers on the 1911. I know it has most all the jigs and fixtures used in repairing them in the shop.
TM 9-1005-211-35 Pistol, Caliber .45, Automatic, M1911A1:
https://archive.org/details/TM9-1005-211-35
Also, you can easily make a sear jig. Just measure the hole centers for the hammer and sear pin, then drill a small steel block with those centers, using the correct hole sizes to match the pins. Buy original pins to use in the jig, as they will fit the hammer and sear correctly. After the block is drilled, and the pins tapped in, slip the hammer and sear over the pins, and visually check the fit. Hone the sear until it has a positive engagement, in other words, when the sear is moved forward out of the hammers notch, it should barely move the hammer backwards. Last, check it in the gun, and measure the trigger pull. If the assembly shows either neutral or negative hammer to sear engagement, it is unsafe, so correct the angle(s).
The best way to measure the hole centers, is to place the pins in the holes on the frame, and measure across them with a dial caliper, then subtract 1/2 of each pin diameter from this measurement. The sum of the subtraction is the hole centers. If you have a frame print, you may get the centers from it.
I would advise looking for a DVD on these, by AGI, for gunsmithing the 1911.