Binnie, I'm sorry I missed your question for so long:
"What did you do to isolate the hole for the exit through the wall...any heat wrap you can suggest? Just wondering. binnie"
I used a piece of double walled stove pipe through the wall, but haven't decided what to use for "packing". There is insulating wrap for exhaust systems available on ebay, and mcmaster sells thin sheet silicone.
Let us all know if you come up with something.
Best Wishes,
Bruce