The second one is Tiger Men: An Australian Soldiers Secret War in Vietnam by Capt. Barry Peterson with John Cribbin. Peterson worked up the Montagnard tribes in Dalat Province. Plenty of skulduggery, with a very conservative style of writing, conservative as in not wasting any words.
Finally, Uncommon Soldier by Chris Masters
I've got Barry's book, I've read the other one by Frank Walker, and I've come to the conclusion that Frank is a bit of a dick head. Need to read the original and have been meaning to get onto it since he died a few years ago.
Masters would struggle to get the same access to diggers these days. His reporting on BRS, VC, MG hasn't been received well. Even if it may turn out to be somewhat accurate.