Back to the OP’s questions. Careful positioning of the underfloor master cylinder and maybe a bit of fabrication on your part and you can make it work. Since you have already modified to a V8 why not just put a power brake unit on the firewall like the later trucks? I believe the clam shell doors might be a bit rare compared to barn door, plus you can “Tailgate” with the clam shells. JMO

Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
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