Just another idea.  What about using "durarock"?  it comes in a panel and
is especially made for high heat places.  We just installed a fireplace
and it had to be placed around the walls of the fireplace box for heat
safety.  It can be cut down to any size like wood, it looks like a sheet
of blueboard and you can find it at any Home Depot or place like that!
Just another, safer idea!
 
Eleanor
[Posted in FML issue 3754]