Airbaged,
Since you have a '39, will you keep the brake peddle under the floor or will you have it come from under the dash? Have you found an idea of what you will be looking for or what you route you will go? From looking at your pics, you seem pretty know how on your build, so I think you'll do fine.
Keep us posted because I like to read up on others trials and tribulations.
You are also going with an automatic trans, so you will not have to worry about the clutch so this set up will be easier to do.
There were many discussions on the very subject you are asking about, but here is one of them
"frame mounted brake booster and master cylinder" from bgharris28.
Bread
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