So in my post above, you can see the backing plate. I added two roll pins to the backing plate (interference fit) and drilled holes in the ball mounting bracket on the QT(slight interference fit) so you can press the backing plate into position with your fingers and it will stay there. I'm running a Centerforce dual-friction clutch setup ... the diaphragm clutch pedal pressure is pretty light so there isn't much stress on the ball stud mount but at high RPM with the centrifugal weights kicking in, there might be flex there and the mounting plate threads would give up at some point. Better to address this now rather than have it fail while out driving on the street.

I started to eyeball the starter mounting and noticed that the upper hole in the mini-starter was bigger diameter than the hole in the QT ... so I whipped up a little reducer busing.