I also noted the condition of the top bearing caps on the grinder. Either a previous owner cut the top caps into two pieces each, or, Canedy-Otto designed the grinder with two-piece top caps. On this type/size of grinder, ring oilers were often used. My own Champion Blower & Forge grinder of this same type has babbitted bearings with ring oilers. The condition of the grinder in Billygoat's photos has me wondering whether C-O furnished the grinder with ring oiled bearings. C-O had a reputation, at least for blacksmith shop equipment, of being top of the line. Of the 'big 3' firms in the USA who built large quantities of blacksmith shop equipment (Buffalo Forge, Champion Blower & forge, and, Canedy-Otto), C-O produced the finest and smoothest running of the hand cranked blowers. Their forge fire pot design was also a notch or two above their competitors. It would be in keeping with C-O's reputation for good design to have used ring oilers on the grinder bearings.
Whatever the reasons for the upper caps being about half the length of the lower bearings, running the grinder as it is would result in grit getting onto the arbor journals and chewing up the works. Hence, going to modern sealed bearing pillow block bearings is really the best option, particularly if the OP intends to really use this grinder.
We have had some threads about the need for good wheel guards on grinders, and the effects of a grinding wheel failure (more like an explosion). I would not run this grinder without upgrading to wheel guards, as the OP intends to do.
Plainly, there is a fine balance point between 'historical machinery' vs safety and practicalities. If the OP intends to use this grinder in regular shop service for a grinder of this size, then he is absolutely correct in his approach to retrofitting or upgrading it.
At the end of the day, the reality is that the OP owns the grinder, intends to use it in regular shopwork, and it is his decision as to what he does with the grinder. Having seen the aftermath of a 14" aluminum oxide grinding wheel explosion on an unguarded machine, I would not be at all comfortable in running a grinder with an unguarded wheel. In working shops, as time marched on from the time grinders like the one in this thread were sold new, people did routinely modify them for safety as well as practical reasons (guards, along with going to sealed pillow block bearings and motor drives). How many of us have seen, or own/operate old lineshaft machine tools (lathes being the most common) that have been retrofitted with brackets, old truck transmissions (or Unidrives) and electric motors ? Not too many of us are about to unbolt the brackets and motors and hang line shafting to drive those old machine tools. By the late 1920's and certainly into the '30's, conversion drive systems for lineshaft machine tools were being manufactured and sold. I have no doubt that close to 100 years ago, people were already converting lineshaft driven machine tools into individual motor drives. Historical value becomes a debatable topic.
The other bright side of this thread is the OP got that grinder to USE. Important word. He is not going to retrofit it with a cafe table top and put it in some fancy dwelling place or eaterie. I stand with the OP on this one.