Gentlemen, I'm looking at a set of complete sidelocks for what is advertised as a 12 ga regular weight Eslie. LC Smith is stamped on the sides with no other engraving, and only one attachment screw, with radiusd top corners on the plates. The observations verify that they did come from a regular weight gun and was likely an O or OO grade (pre-1913), or Field grade if post 1913. Were Field grade (post 1913) guns built on regular weight frames? I've only actually seen them of FW frames. Serial # is clearly visible and if the gun is pre 1913, then according to the Late Mr. Houchins Book, the serial # is only attributable to 16 gauge guns. If the donor gun was indeed 16 gauge, were the sizes of 16 gauge lock plates consistant with that of a 12 gauge? Thanks in advance for any further insight, as I could possibly use some or all of the components as life support for an old family gun (pre-1913) that I shoot all of the time. John