[edit] Note to self; ensure you do click post and not return a number of hours later to discover it had not posted. ...
Not planning to, don't think it was used in Vietnam.... Wiki says 150 was Saudi National Guard?
Finally dug out the Osprey book.
The V150 is post 1969 and is based on a combination of the V100 and V200. I suspect it might look at first glance like a V100 with a big turret, but I suspect would be a redesign.
Plus, as you say - not fielded in Vietnam.
They do seem to have got about.
I blame too much Morrow Project, apologies.