More information on these vehicles can be found on REMLR.
http://www.remlr.com/2Alrpv.html
One of stuarts vehicles is on there described as Brians (or BB's) LRPV. I'm yet to change the page to reflect TommyK's purchase of the vehicle from Brian.
Information on the vehicles is indeed few and far between. An article on the vehicles should be appearing in an edition of the Land Rover Enthusiast magazine very soon. Hopefully the edition after the one that is about to come out.
Richard