Yes ,I had to make the changes to work with the after market mount . When I placed the Gun Parts Corp. scope on one of my original Enfield snipers the scope lined up with no issues the scope cross hair and the post lined up with no cant and the there was no binding with the rings .The mount I have is from SARCO purchased 10 years ago . I have a second one that came from Accumounts it is some what a better in fit . The best ones came from ENGLAND ,but the maker ,I do not think is making them currently . I did not mention that rear ring must not ride up onto the scopes rear bell , be sure there is space between the rear ring and the front edge of the bell where the bell meets the tube .