Gary,as for engine oil selection,it will not matter if you have EGR or not.
Current diesel oil specs are CJ-4.
Kubota ships with 10W30 conventional oil as the factory fill.
You may elect to use 15W40 in your warmer climate as almost all are CJ-4 rated.
10W30 diesel is still fine,as as far as current motor oils go(thin is in!)
There are also many synthetic 5W40 diesel oils out there should you prefer.
Also,I forgot to mention,Kubota is woefully out of date on oil specs in their manuals.
Good Luck!
Nice Tractor.