While trying to decide if I wanted to try adding grips on myself or spend money on having someone else do the work, I first practiced sanding on the frame by removing the seams.

I recommend starting the project this way so you get the feel of working on the material before drastically altering the grip.

Instructions

Please Read Disclaimer

Go SLOW!!!  The longer it takes the better it will come out.

1. Start by grinding the grip inside the red lines, to level it off with the frame.  

2. Once you are close to the level of the frame use the file to level off the grip to the frame (red lines). Notice the trench is still there, it will be covered by the new grip.

3. Now take the new grip and sand off the corners as needed to fit flat against the frame. (red lines mark original shape of the grip) 

4. Position the grip where it should be and mark on the frame where the holes in the grips are (red dots).

5. Drill the holes 90 degrees to the frame. Make sure though that the top hole does not cut into the sear pin hole.

6. Screw in the bushings until they are flat against the grip.  Do not tighten them.

7. Mix up a small batch of JB Weld.  Unscrew a bushing, apply JB Weld to the threads and screw it back into the frame, repeat with the other 3 bushings. Let them set for 24 hours.

8. Because some JB Weld is around the bushing, the holes on the inside of the grips will need to be flared out to accommodate.

9. Install the grips on the frame.  Do not over tighten the screws, keep them snug.

10.  Remove the grips and use the sandpaper to smooth down all the deep scratches.  You may find you want to grind some on the trigger guard for a better fit.