Gerry-
Thanks for the tip...I do appreciate it.
We had a fire today, and all looked good, but I'll certainly be keeping an eye on it. Like I said, it's a temporary fix to get us through the remainder of the winter. I think the thing we have going for us is that it's not in direct "contact" with the fire's "exhaust" and the intake air does flow down the inside of the glass as it makes its way into the firebox.