Thanks for all the advise and comments. I re-installed the rebuildt injectors last Saturday and I swear I have a new tractor. I changed both the primary and secondary fuel filters and found some very interesting stuff in there. It was not good! Rust had not yet formed so I was able flush the tank and filter cans. We cleaned the barn yard and hauled 12 spreader loads to the field. The tractor ran very nice and got a pretty good pull in the soft dirt and a fully loaded 350 spreader. My pants will have to head for the basement as I got a little diesel fuel on me during the filter change. The excessive smoke is gone now and it is a pleasure to drive. I hope to get it to the Badger Steam Show in August this year. The engine hour meter reads 1404 hours. I hope its the orignal meter. <!-- s:D --><img src="{SMILIES_PATH}/icon_biggrin.gif" alt=":D" title="Very Happy" /><!-- s:D --> 

I noticed the breather tube at the right angle before going down the side of the motor seems to have a plug missing and is venting some engine blow by under the fuel tank. Is this a metal fitting or can a guy use a expanding rubber plug to close the tube corner?

I hope my ideas of having to do a complete overhaul are gone now. It runs and sounds fine! I did speak to some guys about re working the head and it is complicated with a diesel relative to the piston tops and the head. I do hear of a lot of cracked engine blocks and water in the oil on these older tractors. I'll count my blessings for now.