I put my probe grommet just beneath the level of the first grate in my UDS. I don't cook much on the second grate ( usually use it for a water pan). You could place the grommet midway between the 2 grates, that way you could use a probe on either grate. I know the et732 has 1 food and 1 grate probe, but with an extra food probe and the grommet in the middle, you could have 2 probes for food (without a probe for the grate temp) at 2 different levels.
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