Mark,
I recently had to change the gaskets and the flanges for the S&S 124 that is in my 08 SERK. I watched that video and what helped me was paying attention to the flange being perfectly flat. The one that leaked was badly warped. When I went to the dealership I had to go thru 4 or 5 to get two that were flat. A couple of them were down right nasty. They had a surface plate that I could use but the counter or a piece of glass might do. I have the 66mm throttle body so the space I had to reach the Allen head bolts caused me to make one real short Allen head wrench to reach. I doubt that will be necessary for yours. I did use some grease and made sure the throttle body was lined up prior to tightening everything up. Just take your time as there is not much room to work, I did have to remove the tank and while it was off I checked the electrical contacts on the Road King console. Let me know if you need any other info.
Good Luck