I have the FTF problem on my two-porter. I decided to do this mod myself, but I am having a devil of a time getting the gas block off. I didn't have a shelf piece so I am using a small framing square. I have managed to bang up the square pretty good and the gas block has only moved a millimeter at most. It's not mentioned above, but does the rear pin (circled in red on picture) have to be removed, too? I would be grateful for any suggestions.