When I saw the image of the vest here, I had a sort of flashback to Ft. Polk around 1995 I saw one soldier, who I recall was a general officer, wearing the vest which I identified at the time as a component of the IIFS test equipment. I didn't ask him about it so I don't know if he was using as a matter of personal preference or still testing it, but he was the only individual using the equipment at the time. I recall he had no other equipment attached to the rear so the laces at the sides were plainly visible and was drawn tight so it appeared he was using it as a sort of back support. It is likely he was assigned to the unit that tested the IIFS, and continued to use it as a matter of personal preference.

The only equipment I am familiar with that was a component of the IIFS test was the canteen covers, which were manufactured in 1988 on regular contracts, substituting Battle Dress Uniform material for the OG nylon material normally used for canteen cover LC-2. Although I am always suspect of wikipedia you may get enough information from that article to determine what components you need to complete the vest. I think it an interesting project to put together a set of IIFS equipment.