As Rapid Robert mentioned, your dimensions may vary! Having said that, I ran a 340 with 727 in my '65 Barracuda for almost 40 years, and all I did was flatten the pinch weld with a large hammer. However, if I had it to do over again, I probably would have stuck with the 904 that I gave away. None of that matters now, since the entire floor has been cut out and frame rails added to get ready for an aluminum 433 3rd gen hemi and Tremec 6-speed converted to a sequential box using a PPG gearset.