Don't know the welding particulars of this. Don't know if this is the area you mention.
CLICK


I don't have any parts to look at. I may be way off of the area in question. But here is a try. Feel free to Kibosh or embellish. Actual shape of threaded plate TBD. Flat gasket will seal. This will look ugly with the hood open.
Attachments
thd plate.jpg (171.06 KB, 111 downloads)


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