I think the hole is used to hang a sign to remind you to disengage the bull gear before you hit the power switch...
Seriously, I have not seen one like that. If you want one without the hole, I have one from a Model 210 that should fit. Send me a PM with your address if you want it. The one I have has a jammed up locking mechanism, so you'll have to swap yours, or repair the one that's in it (could be just needs some oil).
A long time ago, I recall seeing someone on the web who laced a serpentine belt with fishing line, to install it without pulling the spindle. Since there's no metal lacing, it likely wouldn't be noisy, and there's plenty of room between the serpentine belt ridges to double or triple lace it, if strength is a concern. I plan to give it a try using one of my old "low mileage" belts, since I usually change them every 50,000 miles or so.
By the way, the paint job on that headstock is just as nice as that sweet new chuck. Looking good!