Chevrolet Car (1953)

Hope it helps. If you do some searching you may find more info looking for frame repair info. Even stopping at a full service body shop and ask if they have any frame repair books that go back that far. They may let you copy it. :)
Data shouldn't be that difficult to find, I found what I gave you in one search. There are also a number of hot rod shops that build frames this gen Chevy so they may be a source for data as well.
i actually asked a buddy of mine about it who works at an auto body shop, and his shop manager said back then, they didn't have very good records of dimensions, so there is little info