Gear Vendors in a '67 Barracuda, is tunnel clearancing required?

On mine 340/727 combo, I had to "adjust" the tunnel in two small areas. Gear Vendors said to use a ball peen hammer, I used a blount end air chizel and it only took a few minutes. When youre finished make sure you can slide some cardboard between the tunnel and the GV in the places where it is tight to make sure it clears. Bob