Clone tool arm question

[little mac]

I'm nearing completion of my KMG clone and wanted some input re: the hole placement in the tool arm where the contact wheel axle will mount. My shaft will be .750 dia. Tool bar is 1 1/2 sq.
How far from the edge of the tool bar should the hole be ? To clarify, a .750 hole bored ( i'll bore it 751 +.002-0) .475 from edge, will result in a .100 web on that side.
I plan to cross cut the hole on center,with a 1/8 or so slitting saw and cut at least
.100 past the hole.
Anything wrong with this plan and what thread bolt would y'all reccomend for clamping the shaft and hopefully achieve a 1/4 turn release.
Clear as mud ?

 

[SteelSlaver]

KMGs use a 1/2" threaded hole to mount the wheels which are mounted on a 1/2" bolt. Your way should work fine. I would use a 1/2" fine thread (will apply more pressure) bolt to clamp the shaft if done this way. I would drill the 1/2" hole centered around 1/2" back and then drill the .750 hole 1" back. I might make the .750 hole a little farther from the edge, say .50 giving you a 1/8 inch web and keep it just large enough so the .750 shaft was a slip fit. Just my thoughts and I am just a hack who has made and worked on a lot of steel objects. Jim