Finally got started tonight on some actual airplane parts. I began where the instructions have you begin - by "breaking" the edges of the HS-609PP. I used a combination of files and Scotchbrite wheel to do the work.
I only have a small 3M wheel right now, so I need to order the bigger size and put it on my bench grinder. I have some more clean-up work to do on these HS-609PPs but tonight was a good start - still learning.