The camo system was called MERDC. It was used in the mid '70s to mid '80s and was replaced by the 3-color NATO camo.
MERDC info:
https://gurth.home.xs4all.nl/afv/merdc.html
The pattern on the M151A2 1/4 ton is Winter, US & Europe, Verdant. It was the most common patter. Here is a good pattern for it.
Usually, when doing MERDC, I paint the green and dark tan w/an airbrush, then paint the sand and black squiggles with a brush. You can also do the dark tan w/a brush since it is a small subject.
I sprayed the green and hand painted the rest on my recent M818 5-ton tractor.
