The standard way to install the rudder stops is to rivet a metal angle piece to the outside, aft end of the fuselage. I opted for the Flyboy Accessories internal rudder stop. It gets bolted into the vertical stabilizer hinge and does the same thing as the metal angle, but is made of delrin and is slightly lighter because I weighed both :) But I don't think the airplane will fly too much faster with 26 grams vs. 35 grams - and when the bolts vs. rivets are weighed... well... So in converting, I had to go back to the rear fuselage skins and 2 holes in the rear bulkhead - which were purposely left un-dimpled for the angled stops, and now they can be dimpled so that the plug rivets can be installed. I didn't want to pull the skin off the airframe to use the DRDT2, so I left them on and used the pop rivet dimple dies. 12 headless nails later and I was done.