Dear Stephen Tagliarino:
Thank you for posting your question on History Hub!
Post Office box holder records are not considered permanent Federal records and therefore not accessioned into the holdings of the National Archives. These records are destroyed about 2 years after the contract for the box ends.
You could use census records to trace your great grandfather back to when he was a child with census records and see what the address was there, but usually census records are not for postal boxes because it is not a physical address. Information about census records can be found on our website at https://www.archives.gov/research/genealogy/census/about. Many of these records have been digitized and are available through our partners or our catalog. For additional information about accessing these records, you can visit our website.
Depending on the year, there might be local White and Yellow pages. Some directories are available online through the Library of Congress.
We hope this information assists you with your family research!
On Ancestry there is a family tree for Giovanni Tagliarini on the manifest it lists his wife's arrival Oct-3,1903 on the ship - Manilla- with his 4 children on the comments on the manifest she is going to see her husband Giovanni Tagliarini in Bunkie, LA Box-51. See link