If I understand correctly, you're trying to grease the zerk that's in the "web" between the trunions, and is pointing straight out between the trunions? If so, I have never seen one that couldn't be greased with a regular gun, but then I haven't worked on everything either. Are you sure it's not just a matter of rotating the driveshaft until the zerk is in a spot where the space around the zerk isn't being "pinched" by the yokes?
