rethreading went fine, with the how-to info
removing the power steering return line helped greatly

unfortunatly in removing the lines from the oil cooler one nut galled and took 1/2 the threads out;
snugged it up hard but can't pressure test 'till tomorrow, waiting on other parts

- just in case, anyone have a used oil cooler about ?

this is the 5th 300SD I've had, have 2 at the moment, and each has had a busted air filter bracket at less than 180,000 mi;
this one had been welded, a waste of time
MB should mount a spare bracket in the trunk