cayugad,
I was so impressed with the ingenuity of the idea that when I was out shooting the other day, I pulled the jack out from behind the seat of my truck and used it insted of the 1 foot piece of railroad track I had been using. It performed flawlessly. I am going to the junkyard to get one and mount it on a piece of heavy board. I use a 45 degree angled cut piece of 4 x 4 block about 8 inches long for the buttstock rest. It can me moved in or out for fine elevation adjustments.