BBD, I will do my best to give you the procedure that worked well for me. First, I did set the lash on each valve as I finished the cylinder. This adds some time and engine barring to the procedure, but mine needed doing anyway. I also did NOT replace the stem seals. Mine were 105K old but Cummins said unless I had a problem, they would be fine. I did use new gaskets and o-rings on the valve covers 'cause mine were stiff and starting to seep a little oil. Cummins did recommend doing one cylinder at a time so as not to loosen too many head bolts at one1 time.
1. To find TDC on #1 cylinder, remove valve cover and bar engine clockwise( looking at front of engine) until intake valve just goes closed. Then turn engine over ½ turn(180 degrees). This should put cylinder all the way up on #1. You should be able to shake rocker arms on both intake and exhaust valves.
2. Remove both bolts and rocker arm assembly, being carefull to not bring push rods with it. Place a rag or towel over as much of the engine area as possible to keep from dropping anything in engine.
3. Place a hammer, handle down, on the exhaust valve and push down to insure valve hits the top of the piston. If it does, put valve spring tool on and compress valve.
4. Once compressed, bump down on tool and valve to loosen collets. Retrieve collets with magnetic retriever being carefull not to drop. Slide spring off stem.
5. Check valve stem seal to insure it is still in place. Compress new spring and slide over stem. If valve drops too far, the engine can be barred one way or the other with valve on piston to ensure you are all the way up with the piston. It may be necessary to slightly compress the new valve by pushing on top of tool because the new springs are longer that the old ones. I also "screwed" the new valves into the compression tool as far as I could before I started cranking down on the tool. Yours may work differently, but my KD tool needed this help.
6. Drop collets back into the collar. Make sure they are both in place before releasing spring tension. Once released, remove tool and tap on top of valve spring with a mallet to make sure they stay in place.
7. Install rocker assembly, making sure push rods are in place. Torque small bolt to 18 ft/ pounds and large bolt to 90 ft/pounds plus ¼ turn. You may want to check this in the book. Set valve lash now, if you plan to.
8. Put cover back on and torque to 18 ft/pounds.
Note: If you do not plan to set valve lash, you can replace exhaust valve spring on #6 cylinder before barring engine again because #6 is at top when #1 is. Once finished with #6, bar engine 1/3 revolution and do #2 and #5. Then bar 1/3 revolution and do #3 and #4.
9. If you are going to set valve lash, bar engine one revolution and now # 6 should be all the way up with both rocker arms loose. Or you can follow the firing order using the same concept as before. Hope this makes sense.
Note: Make sure to remove the rubber stopper above both #6 and #5 to make it possible to remove the large bolt that holds down the rocker arm assembly.
This is as clear as mud, but let me know if you have any questions. There is also an old post by DieselB59 back in July where he goes through the same thing.
I have never used the air method.
Big John
Attention: TDR Forum Junkies 
