Model 75|Winchester .22 Rim Fire|Forum|Winchester Collector

I have a model 75 sporter which is as new in every way.  My question is regarding the Weaver scope.  I noticed that the rear sight has been radiused to accept the scope face.  Was this done at the factory?  The way the scope tube has been relieved to accept the 2 mounting screws is a precision piece of work which wasn’t for the faint of heart and I cannot find anything on Weaver to suggest that it was made especially for the 75.