I have a copy of the original Off Road Magazine issue, which has their overland debut in Turtle I, their Land Rover Series II.
Back in the 1970's I used to devour every 4wd magazine I could find (the big 3 were "Four Wheeler", "Off Road Vehicles" (Later just changed to "Off Road") and my favorite was "Pickup, Van and 4wd" or PV4 for short.
The first two are still in existence in some form, PV4 has been dead since the early 80's.
Anyway, I actually had that same issue with the Westcott's detailing how they came to choose the LWB Landy 109, how they equipped it, and so on.
Unfortunately, after I went into the Army in 1980, my mom moved to a new house and those old magazines apparently got thrown in the trash.
I often wish somebody would scan and digitize those old car an 4x4 magazines. Lots of good info there and better than that, magazines, being periodicals, have a way of capturing the "zeitgeist" of an era better than retrospective histories. Honestly, if someone were to digitize those and make them available on DVD-ROM or CD-ROM, I'd buy a copy, for sure.
At least I still have my copy of the "Off Road Handbook" by "Bob Waar" from about 1976!
