Master cylinder/booster on 440 Duster

Mine was originally a front disc (kelsey hays) but manual brake car, so I ordered this master which appears to be for that type of application. I am running all 73 Duster big bolt stuff now. I played around again yesterday with my power kit, and it may clear but just barely. There is alot of adjustment on the 4 mounting slots, tons actually, so as long as it does not bind up too badly against the grommet I might be ok... Either way if the 1" bore master works I have a backup plan