Beta Archive removed it a while back from their FTP as explained at https://www.betaarchive.com/wiki/index.php?title=Windows%3AChicago%3A56. I have tried this fake in many virtual box and always fails to install, while 58s works flawlessly in virtual box. Since this site is dedicated to historical preservation, it would be in it's interest to remove a fake that is known not be real. Also, it isn't on TCB, so it's pretty safe to assume it isn't real.
TCB is an acroynm for thecollectionbook.info, a website run by Beta Archive member Robert Jansen, who uses to keep track of Windows Builds, as well as provide information about those builds and show solutions for some problems such builds may have.
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(I also find it quite interesting how the archive sizes of both 56 and 58s are less than 10MB)
EDIT: According to BetaArchive, builds 73 (not 73g) and 78 are fake as well. WinWorld still has both of them.
EDIT 2: @whistler2250 what is TCB?