Did You read AND comprehend My post? IIRC, the Offy is a square hole w/o that intrusion, & My Cliffy has that plate fabbed for a sq-bore. I overlayed the other adapter to show the base pattern match, & yeah, I'd mod the Cliffy IF I wanted to stick a spreadbore on it. That said, You can't always tell what air's gonna do just lookin' at it. If it doesn't immediately obstruct the throttle blades/discharge, it could shock You & run better than carvin' away at that makin' it "better", wouldn't be the 1st or last time a "WTF?" were induced by such......