Spread Bore On Offenhauser?

These I purchased from another Rusty on .org, and were part of Bob Stepp's collection of parts. Appears to be a modded std spread-to-square 'dapter, needs a little professional "refinement" to line-up w/base screws, & a little work w/a spot-face/end mill to finish for some allen-head screws. Placed over other for reference.