I read a hand full of guides on the subject, but I found this "how to" video to be the most comprehensive: Part 1, Part 2. After lapping, both my CPU's integrated heat sink and the main CPU heatsink (using 400-2000 grit), temperatures really didn't seem to drop (disappointing). Mechanically / theoretically it is indeed a better setup as there is much more uniform physical contact between the two parts, but apparently this CPU just doesn't get hot enough to utilize such a setup (afaik, most people who do this are overclocking their CPU's).

In the end, I'm still happy I did this process for the great learning experience.