Doc,
IMO yes to both. And I would suggest for sure to take the injector pump to a qualified dealer/rebuild shop who can bench test it correctly.
However, on the valve adjustment, it was a lot easier to do than you think. Your manual should have the recommended clearances for intake and exhaust and you can set them yourself. It is a great way to become more familiar with your tractor in a manner that exceeds minor repairs most guys limit themselves to because they don't think they can do it. It also gives you an appreciation and new level of awareness so as to recognize the slight differences in the way the engine runs. It will make you end up taking better care of the tractor because you can now realize when it's running "perfect" or it's not...and you can tell the difference.
All you need is a couple of wrenches, feeler gauges, a new valve cover gasket (that you can make yourself or buy) and the clearances for the valves. Also need to identify which is the exhaust and intake valves AND how to determine top dead center of the cylinder you are adjusting. Usually, the intake has a little less clearance than the exhaust valve, but it will be specified in your manual as well as how to identify the valves and how to find top dead center.
I am by no means a diesel mechanic and am not trying to pass myself off as one. I have worked on my own cars for many years, but the diesel was new to me. If you are interested, I documented my valve lash adjustment here,
VALVE LASH ADJUSTMENT and it was a learning curve for me but very doable. Again, be sure to follow the instructions in your manual, but do it and you will enjoy the self satisfaction when done.
Hope that helps,
Rob-