I went to the scrap yard and found a peice of 7" angle iron. It is 5/8" thick, and 40" long. I cut it in half, welded two peices of flat stock on the bottom to hold them at the proper spaceing. I bought a section of 5/8" stainless all thread cut it into 9" peices. Then I bolted one on each corner, and at the bottom of the all thread I bolted some 2" scrap peices of angle iron. Then embedded it in a 30" by 30" by 24" concreat footing. My tower and gin pole weigh about 1500 lbs with the machine on top. The hinge works great!
This isn't the best picture but you can kind of see it. the footing is below the surface of the ground to help because its allready 18" and 36" above the side footings, and 5' and 6' front to rear. The guys tighten as it goes up, so I stood the first section plumed and tightened the guys. Then when I raise the tower the higher it gets the less play there is in the guys. It actualy goes up and down very smooth.