Hey there Big Hext,
I squared off the vertical part of the grip where it fits into the frame behind the trigger guard (very little sanding. I used a sanding block) then I worked on the horizontal part so it snugged in at the top (Almost no sanding). Holding the grip tightly in place I used a sharp pencil to mark where the grip was past he edge of the frame all around and sanded down to the line. I took my time and did both grips. I then glued the spacer to the eagle half and let it dry then I sanded the spacer down even with the frame and added the other side. I had very little final sanding to do. Like I said the directions are very good. This is my third set of grips from the Gripmaker.
Nine Toe Jim