Foam won't help dispurse the heat, if anything it will increase it.
Try filling the gap with a copper shim, they sit around the chip giving greater coverage.
What coolers are your using.
My advice is to get some Artic Silver II heatsink paste, and get yourself a decent cooler - preferably an Alpha or Thermalengine, or the other options available are to make up a water cooling system or buy a peltier, that should bring the temperature down a bit.
You should invest in some system cooling also. Retracting the heat away from the chip is no good uless you can get rid of the hot air that is now inside your case. I recommend that you get some 80mm - 120mm fans for your case, usually 80mm holes and casings are built into cases for the front and back, one sucking air into the case at the bottom and the other extracting air from the back.
Slot coolers are also available, they take up a slot where your PCI/ISA cards normally reside. These although cheap, can really reduce system heat.
With regards to the 92mm fan on a FOP32, the only way to do this is to get some metal sheeting and create a tunnel for the air starting at the size of the heatsink going up to the size of the fan (leave the heatsink fan on also). Or get some tubing from a air duct or washing machine/tumble dryer air duct.
Hope this helps.