Local machine shop just rebuilt 4 of these (or at least similar) for a farmer. They had to cut out some old bushings, rebuild some holes, etc.  He had a couple hours in each arm. The tubing for the bushings is something special ... like $ per inch special.  But he figures he will save the farmer one or two thousand dollars over what Mother Deere wanted for the replacements.

Is there any way grease zerks could be installed there?