I've had them apart before, and replaced bearings....
The fittings may or may not have anything under them. The last one I did, I had to replace the upper motor bearing. Kind of a pain, glad I didn't have to go farther.
I found that the bearings were all sealed, and the oil/grease channels led nowhere.
We use it for driving a temporary test jig for unrelated equipment (high speed generators), so we got a bearing from McMaster and stuck it in...... we are not putting many hours on it, and not using it for routing..
Ours was an older one, and it did NOT come apart as I had expected...... I had to pull the little fan assembly, and the parts as they came off were NOT what I expected.... But we had no info, and neither Perske nor their agent ever even acknowledged our questions.