Driveplate Assembly Bracket

I found that driveplate can wobble if I use a propeller to assemble it, because the front and back hub surfaces of some propellers are not parallel with each other.

I use a metal flat corner brace for this purpose. Both surfaces of these corner braces are parallel. I cut a washer from thin plastic sheet and sanded both sides, then open a hole with a paper punch. I place this thin plastic washer in front of driveplate to avoid flattening knurled surface. Two pieces of electrical tape can also be used for this purpose. Then I place corner brace and two washers. Flat corner brace can also be attached in a vise.