Mmmmm..... the Canton and Moroso type have a female threaded center bolt, which goes onto the nipple of the standard filter setup, and are sized with a seal diameter that matches the oil filter mount pad on the filter plate. I am not sure you can mount it without the plate.... it at least needs a nipple, and not sure the gasket would match any machined surface on the block. (Edit to add: I just check a 360 block and there is no machined surface for the remote adapter to seal to without the filter plate.)
IIRC, we mounted our Canton adapter WITH the plate. Yep, looks like we did:
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