It's funny you should mention the blades looking low MF. Last month, I was doing some work on my old Victa Monaro with the old style blade disc. I didn't have any of that style Victa blade, but I thought for now I will just put on some of the skinny Rover blades (same hole size and overall length).

I thought they looked like they were much lower than the front skirt, so I have left it without blades (not using it yet). Its strange because the blades it actually takes are the same length