Well, here is an update:

It appears that the Marksalot "blueing" will work WITHOUT having to sand the crankarms! I did a test on the back side of the drive side crankarm and what do you know, it sticks just fine AND looks fabulous.

It's looking like I can do the whole process in about an hour and a half.

Here's what I started out with:

Picture #1: Brand new Shimano Dura-Ace FC-7800 crankset
Picture #2: What you will need to do the job