Greg didn't say I could give out the patch, but I doubt that he would mind.
In a backup copy of pt3.code0,  look for a byte sequence:
  A9 09 8D 38 C0 A9 42 8D 38 C0
change to
  A9 09 8D 38 C0 A9 4A 8D 38 C0
                    ^- change 42 to 4A

In Greg's pt3.1 pt3.code0 file this was at offset $1DAB, in my pt3.code0
file this was at offset $1D89, so look around those offsets.