8) The top edge of the primary and secondary trigger sear must be sanded smooth so it won't cut into the Delrin hammer guide, this is vital to the life of the guide. This step must be done correctly. (Note that a coarse and fine grit sandpaper have been supplied with your kit.) Use your finger and the coarse sandpaper first and sand the sharp edge off the tip of the primary sear, do not sand to much, just enough to make it smooth. On the secondary sear sand the corners smooth, you will have to support it so it doesn't move back and forth while your trying sand it. Putting a hex wrench across the back of it works good for this. See figure 2. Once you are satisfied that they are sanded properly use the fine sandpaper to polish both sears.
Test the sears by holding the PRO-COMPv.3 hammer guide on top of the sear parallel with the trigger housing, while pushing down slightly slide the bolt back and forth, it should slide smoothly without shaving the Delrin guide. See figure 1. Make sure absolutely no Delrin is being shaved off this is VERY IMPORTANT! See figure 4 for rest of trigger upgrade.

9) With the receiver disassembled and cleaned, use your 1/4 inch drill bit and drill through the existing 3/16 inch holes as shown in figure 2. Test fit the quick strip pin, it should be a snug fit.

10) Now you must deburr the rear of the receiver. Feel inside the rear of the receiver for any sharp or rough burrs that might scratch the new parts when you install them. This is IMPORTANT! If you feel any burrs you must smooth them out by scraping them with a pocket knife and sandpaper. Make sure you check the upper bolt hole also.

11) Once the trigger sear is sanded properly and the receiver is deburred its time to wash the trigger and receiver again to remove all the shavings. Any shavings or sanding grit will cause unnecessary excessive wear on your PRO-COMP parts.

12) With everything clean and dry, slide the PRO-COMP cocking knob and upper bolt system it into the receiver, it should slide in smoothly without binding, if it does bind check for burrs. With the system in place the upper bolt should slide back and forth freely, if it doesn't check for burrs. Once the system fits properly you can remove it for now.

13) Now it's time to reinstall the valve using the new valve spring that came in your kit. Use the stiffer of the two to start with.
This is a good time to inspect the cup seal and valve housing O-ring, replace them if the if they are worn. Apply supplied oil to O-ring and install the valve, set it in the 12 o'clock position (largest hole setting). Install the two supplied valve retaining screws and nylon gaskets and snug them down, don't over tighten them. These will eliminate wasted blow back pressure that escapes through the screw holes.

14) Put a drop of oil that came in your kit on each of the pivot points on the trigger mechanism and reinstall trigger assembly and grip on to receiver.

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