Al, Thanks for the info.. it will be useful when I get the time to tear into the problem..

No, the motor is not MDS...

IMO, this is worse than just the hemi tick and it has all the symptoms of a collapsed lifter.. meaning its a loud rapid tick until the oil pressure comes up, then it goes away.. At first, it was only noticeable after the truck sat over night, now it is present after letting the truck sit for an hour or so...

It looks like I have a weekend of wrenching to do.. soon!!