The place for this question is indeed the "Ships" section of the Forum.
But I'm not optimistic about getting an answer. I don't know of anybody who carries the part numbers of a big model like this one in his/her head. It's quite possible that the part doesn't fit anywhere; Heller sometimes includes pieces that were made for other kits.
If you can post a photograph of the part in the "Ships" forum, maybe somebody can help.
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