Can't help on question #2.
But question #1:
I purchased a Wilson Speed-Chute for my Kimber and blended it in myself. I used hand files to prevent any high speed screw ups I might get with a Dremel. Followed up with progressively higher, finer, grits of sandpaper. Used a black Sharpie at times to keep better track of where material had and hadn't been removed. To be honest though just feeling with your finger will give you better feedback.
I haven't bother with a refinish on the filed area yet as it can't be seen and the body filed on is aluminium so I'm not to concerned with corrosion at this time.
I'd say the hardest part is making the first couple of strokes with the file. After that it's too late to go back.
Edit To Add: I used small fine files. Sometimes called jewelers files.