There must have been only about an inch of clearance from the original amp, however the back of the amp had more free space with the open part around the capacitors. Now with the enclosed design there will be less total space behind the port. But the air flowing into the port will be more uniform. I guess I will just try cutting the port tube down and leave about an inch or so with the port flare. I guess I won't have to worry about chuffing to much, and maybe a lower tune but less output.