Enviro Ceramic Wool Replacement - use leftover chimney liner?

Like a lot of Enviro stoves, my old EF2 has ceramic wool behind the center panel of that 3-panel wall in the firebox. I did a deep clean yesterday, and the old wool is nearing the end of its useful life. I have quite a bit of chimney insulation left over from the install. It's Superwool Plus 3cm with a foil lining. I'm tempted to use a piece of it to replace the old ratty stuff. It looks like the same thickness, the only difference is the foil.

Any feedback on this idea? Any thoughts on which way to place the foil side? I would think the wool should be closest to the heat source.

I hate spend money I don't need to, but will bite the bullet and spend the $50 for a tiny piece of ceramic wool if need be.

 

Well I went ahead and did it. The foil peeled right off, taking very little of the wool along with it. The new material looks to be a little over 1/2" thick whereas the old stuff was closer to 3/4" - but the new material has the advantage of not being partially burned and falling apart all the way around. It's rated for 1000* C continuous duty, and it fills the space so I'm thinking it's at least "good enough for now."