Once I got to a point when the pad fit neatly in the opening (still overlapping the edge of the original foam a little), I sprayed the bottom part of the pad with all purpose adhesive and placed it back into the opening. I noticed a narrow gap right behind the gel insert so I glued in a strip of standard firm foam. Once the glue set, I covered the entire exposed foam area with the thin foam fabric (I decided to do this to eliminate any noticeable transition between stock foam and the polymer insert). I kept the fabric stretched and wrinkle-free, stapling it back to the seat pan (I did not use any glue for this foam fabric).
Once the foam fabric was securely attached to the seat pan, I trimmed the excess using my utility knife.
Lastly, I pulled the original seat cover back and re-stapled it to the seat pan, re-using the original staple holes as much as possible to keep the entire job clean.
Today, couple weeks after completing the mod, I finally decided to take my bike out for a ride, I’ve done about 120miles with very little soreness. (I would compare the 120 mile soreness to what I was experiencing at 40 miles with the stock seat). The gel-like consistency absorbs lot of the vibrations and relieves the pressure points without making the seat too soft.