Mine in 1950 did too. Same system. It's 3/8 rod and available at any good hardware store. I put them back since the PO had cut them out for some reason. I do not know the answer to your question, other than in my opinion, there is no argument for lessening the structural integrity of the core support system.
The 'some reason' usually has to do with putting a new style 235 in, and the radiator needed to be slid inside the supports channel. Hope this helps!
