1978-80 ford fairmount Master Cylinder ($40), it has brake line fittings on engine side. I haven't done it myself, but it was a suggestion from another teambuick member. I looked at it, and it looks like it may clear.
Other option is upgrading to power brakes. when you install vacuum booster with GM factory bracket , it moves the mounting for master cylinder high up away from chassis. If you have low vacuum, from wild camshaft, then this wouldn't work.
These are suggestions, which I haven't tryed. Post it if you figure it out.
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