Will M3 door sill fit in 325i (pre-LCI)?

[Traveler]

I wonder if anyone can answer definitively whether an E90 M3's door sills would fit in the 325i (pre-LCI)? I am keen to do a custom door-sill insert mod, but was told by the maker of the custom insert, that their template would only fit in an M3 door sill. Hence I am now considering getting an M3 door sill (replica should be ok too, since I am going to mod it anyway) in order to fit the custom insert.I've attached a pic of a door sill to avoid confusion.