The Great old P-17 Enfield.

[Gil Martin]

I agree with Joe in this case. davemarse indicated that he did not know the former owner of the rifle, so who would he ask regarding the sight holes? If the holes were drilled for an obsolete peep sight, then Joe is right on in recommending a visit to a gunsmith or gun shop. No one suggested drilling more holes in the receiver. Joe outlined what appear to be logical steps. All the best...
Gil