If I follow you correctly, you want to install a unit designed for under a built-in stove, but you won't have a stove over it. It's possible that the top of the "under" unit is not heat shielded very much, assuming that the metal bottom of the stovetop will take the heat.
The appliance mfg will specify what can be above, below, and on the sides. You need to check the specs for the individual unit you are interested in. Unless it it clear from the specs that you can have wood or air above it, don't assume it will work.
I assume there is some reason you don't simply want to buy the proper unit for the installation?
YO! gotta say YO! if you're from Philly [ROCKY]. we got 28" and another 18+ coming tomorrow... i go to Maine,fishing, really beer drinking, every year. friend has camp on Junior Lake; Springfield/Lincoln?? Gods country up there.....wonder what our UK friend really meant.
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