There are a couple of ways to lower the profile. The first involves cutting the top of the feed tube down so there is only enough tube left above the window to connect an elbow to. It will lower the profile, but relocate the hopper more towards the middle of the gun.
The second option is to remove the powerfeed from the side of the gun and solder a new low profile feed tube on. You will have to make the feed tube as well. This is obviously the most difficult option and should only be attempted if you have the skills to use silver solder and have some ability to handle metal tubing. There are guys here on AO that can do that modification for you.
Except for the Automag in front, its usually the man behind the equipment that counts.