I am not sure if this will help but when I worked on my 351C Mustang (many years ago) I dealt with Glaziers Mustang Barn (a big Mustang restoration house here in Pa), and someone there might know. I don't have their number but I think they are on the web.
Maybe at www.glaziersmustangbarn.com. Search
for Glaziers and you might find it. Hope this helps.
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