ventilation fan vibration isolation help needed

I will be putting two exhaust and one injection fan in my cabinet to properly move air. Two will be mounted horizontally and one veritically. The trick is that I work so hard to get the cabinet isolated from vibrations that by adding a fan, I'm added micro vibs to the cabinet. The fans are 4" radio shack fans running at 6 volts instead of 12volts in order to slow them down and reduce noise yet still move air. I was planning on using placing a sorbothane grammet (if I can find some) around the screw that is screwed into the cabinet and it would hold the fan about 2mm off the cabinet. Any other suggestions. I want to keept it simple but yet very effective. Thanks Troy