I have not been able to find any pics of the putnam frame lt 250s either. The old site had a scanned article on one from a 1994 issue of 3&4 wheel action. I remember the origional article. It had modified kx500 shocks all around. The front geometry of the frame was changed to a narrow front end with long a arms.
The bike was supposed to have around 12 inches of travel unloaded but it had tons of sag to sit at a normal low mx ride height. State of the art in the early 90s, commonplace today on mx tracks.