Suspended Ceiling and Duct Conflict

Thanks guys!
Tried cutting the box area off a cross T (LOL). Took multiple cuts in both directions one snip/piece at a time. It wanted to cause the face end to twist. The box is just too stiff and will not curl with the snip like a flat sheet would. Took a while and got through it finally but it wasn't pretty. Covered the sharpies with some high speed aluminum tape (left side of picture).
So I tried cutting angled notches out of the box on the main T and bending the box over 90° (right side). It seems to have worked well enough (for who it's for so far) and I think I may try to use it to run a couple screws through to the duct and the panel still fits.

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I had thought about 4' panels in the beginning but decided against as I knew it would be tight fitting. Even 2' panels can be a pain to get in or out with the clearance.
Trial fitting. Panel at top of picture is in the "adjusted" T's..………..
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