Shockwave clearance question

[59Apache]

Replacing my coil overs with a pair of shockwaves in my MII front end and wondered how much the bags will expand with air in them. How much clearance around them should I be looking for?

[Milkcrate]

The Mustang II based Shockwaves will expand to 6.5". Someone once told me to use the "Rule of Thumb", meaning you should have 1" of clearance (the width of your thumb) clearance when aired up.