One correction for above list.
"18 Inch Masport / Morrison Hardened Lawn Mower Blades & Bolts Part number # 529594"
Turns out these are the wrong blades. I was told by a mower shop that they would fit, but the hole diameter on the blade is a couple mms too wide. Also the curve on the blade is not sufficient to reach below the disc. They would be suitable blades if only the "step down" bends were greater. But even then it would be a case of having to alter the bushings on the disc to suit the bigger blade hole.
So it looks like Rover blades are still the most suitable replacement, e.g. # A01118K & # A00672K. They can be mounted flat against the bottom of the disc in the same manner as the original Southern Cross blades. Always use high tensile bolts (Grade 5-8) with high tensile washers and nyloc nut.
Last edited by vint_mow; 16/01/17 11:53 PM.