On pages 2M14-16 in the workshop manual and lists the requited lockup pressure and adjustments. You need to download a copy of the WSM from Kubotabooks. The control valve will external, on the side of the transmission case (as is all Kubota's).
I didn't really want to look but I did because I have the time.
Thanks. I have the manual. I値l check it out when I get home next week.