Norm that will help, i think yours is a type 1, which has little bits on the axle housing for a predticta set up, the type three doesn't have the edge part according to
Vintage Mowers.net , I think this mower is based of the 3rd type because as it was the last released Victa, i have been told the kirby was released in 1960/61 so it would make sense to base it of the 3rd. I might still look for the 3rd type of base to compare more.
Yes the holes on my kirby mowers have been like that, i have been getting an eye for kirby mounted engines haha.
I will ask him to try and find a kirby for it in his piles of broken mower parts.