Wayne Parham Messages: 18787 Registered: January 2001
Illuminati (33rd Degree)
Stacking is usually determined by the environment. One of the best arrangements is all four standing side by side in the center, another is two on two, on their sides. Put the mouths together and lay them on their sides. Then set another pair on top of that, again, mouths together. The cooling system will work even if there is no gap between cabinets but it obviously wouldn't hurt to have an inch or two gap between them.