Dunno if it runs that far back but through the late '80s and early '90s Ford flirted a lot with two suppliers of racks, TRW and official Ford ones, while they both follow same basic design lots of times the parts did not interchange, and why the parts books often ask the question, 'TRW, or Ford'? And with no identifying marks on racks to proclaim which maker. It could be a headache.