You will find adjustment and tune up info here:
ch-part.com/i.caterpillar/reg012220002/

More updates and questions. I am happy to report I drove it out I
of the shop and moved a little dirt.  It sure was fun to hear it start and feel it move. One of my concerns is low idle, I am not sure if the governor is working. 
when moving the throttle from full to the shut  off detent the engine dies about 1/2 way there. I can get it to a low idle if I carefully reduce the throttle lever but if I do it quickly it will stall out. It will start right back up no problem, warm or cold no difference. I did nothing with the injector pump during rebuild. Tractor serial in 04z00461, the engine serial was ground off so I don't know if this is the proper pump. Should the tractor maintain low idle when the throttle is at the shutoff detent?  How is this set ?

Hi Team,
you have a new scroll injection pump and governor that has a damper mounted in the rear face of the governor housing
A picture of one on a similar larger engine should show where it is located.
First try and screw the little damper screw out 2 full turns and operate the engine to hopefully clear any accumulated sludge from the oil damping system that is fed via a trough in the Gov. Hsg.
If the trough is clogged then you can likely clear it after screwing out the damper screw and blow back with air, or if still clogged screw out the body of the damper and repeat with the air. The screw and body can be removed but will likely need a new O Rings--de burr the edges of the screw hole before re-fitting and the screw the damper screw lightly home and from memory open it again around about 1/4 to 1/2 of a turn.
   With the engine at operating temperature test for stalling and adjust until the engine does not stall but does not start to hunt--vary engine RPM's up and down.
  Later you may need to fine tune the damper screw when the engine is cold if it stalls due to the screw being closed too much.

If this does not work then the governor weights etc. may be flat spotted and their thrust race indented so it will need to be inspected--extreme care needs to be exercised when refitting the main housing as one or more of the gov. weights can disconnect and destroy the governor assembly--early units had a shield that prevented this and for some reason Cat discontinued the shield usage.

I only have images for a 3306 engine but they are the same design governor.
Section DD is the Damper assembly--other image is for the  Low Idle Adjustment location should you need it.
Hope this helps.
Cheers,
Eddie B.

So I parked this project for a while, now time to get back to it. I tried adjusting the damper screw, no change or response at all, I did remove, clean, and blow compressed air through that hole, installed new o ring and tried it, no change ,Also removed back cover and cleaned oil passages, I did not see anything out of order but I am not a governor mechanic Today I started it, started instantly after sitting 3 months, I removed the damper screw with machine running, oil slowly dripped out.. Side notes oil pressure at 50 psi.
I assembled this engine myself and was careful with all the o rings between the oil cooler / block/injection pump, could I have missed one or maybe one fell out? I do not see an oil leak in the oil cooler area. I do not know if the governor worked before, I got it as I bought it dead. Looking for advice on the next step.
One more question, what is the simple option for a tachometer to set proper RPM, is there a handheld that works with the drive on the back of governor? TIA

if you can access the crank pulley a optical tach(non contact) is available fairly cheap through abw tools and it relies on a bit or reflective tape placed on the pulley to reflect the laser and thus give a reading. we have one, they work reasonably well.

I agree on the photo tach. Cheap and you only need to be able to get a 1/4" square of reflective tape on the crank pulley.

Anyone with thoughts on the governor not working, Should I have a large amount of oil spraying out when I removed the adjusting screw ? I was hopeful EDB would chime in, hope he is doing OK.

Also, re the tachometer, is the output on the governor at engine speed or 1/2 engine speed ?

on the crank pulley is at engine speed. the governor can be different due to the gear drive ratio. i dont know if it is or not. getting a helper to take a readingv from the crank will allow you to set the stops correctly