I need to know exactly where to locate the top edge of the upper wheel assembly horizontal support arm and mark that off on the vertical support.
For that we need to measure the distance between the shaft or bearing centres plus allow for thickness of the tyres and then subtract from that figure enough slack clearance to allow the blade to slip onto the wheels.
To measure the centres the blade needs to be mounted on the wheels, don’t want to fiddle with something that has very sharp teeth so as before I’ll use banding tape in place of the blade.