Did you find a corner plate ? I need one for the right side 18' hardtop 58.Bladeguy here, I am restoring a 1954 12' Crestliner and am looking for one aluminum transom corner plate, I would take a pair if available.
EDIT: Please dont post email addy or phone # in the open forum. Thanks John
Problem is when you say crestliner. You get ford parts !Ebay maybe your best bet, look for:
Transom corner cap