I just checked the motor I bought and I do not think they ever have been adjusted.probably 30thou on the intake and 50 to 60 on the exh just from how much I can move them.Motor had 170k on it.

 

12 valve should be 10 on the intake and 20 on the exhaust. go to dodgeram.org and you should be able to find it. I bieleve every 60 thousand miles.but i would do 20

 

I've found the first two valve adjustments at the recommended 24k to be the most important. After that the interval could be stretched to every 100k or more as they rarely need further adjustment after the engine is broken in.