No manual was ever produced as far as I'm aware and certainly not a 'VW' issued one.
I don't have my 'standard' Beetle manuals at hand, but I don't recall any reference to the Hebmueller in any of the 1949/early 1950 instruction manuals I own.
The 1949 dealership parts manual features all the Heb panels with part numbers.
47 Beetle, 56 UK Karmann Cabriolet, 56 UK Beetle, 57 UK Type 2, 59 UK Beetle, 66 UK Fastback.