I made mine using a drawbar from TSC like KML suggested. I used a hole saw to cut the 2 round ends of the oblong holes on each side of the barrel and finished the cuts with a saws-all. Slide the bar in place and seal the gaps on the inside of the barrel with duct tape.
While I was at TSC, I grabbed a stabilizer bar, some 1/2" all-thread, nuts and washers. I cut the stabilizer bar in half, drilled 3 holes in each half for the all thread (4" from the factory hole, and then 2" and 6" in from the cut end). The all-thread was used to hold the bars evenly spaced, and by using 10" pieces in the lower holes it works as an anchor in the concrete. The factory hole was left to the top for the top link, and one 4" piece of all thread a few inches below that holds the bars properly spaced. On at least the top all-thread you'll need 4 nuts (one on each side of each bar) to sandwich it in place holding the exact spacing and providing strong support when in use. I kept the bars tilted forward at a slight angle, off center and towards the tractor side of the barrel a few inches too. I got the measurements for the pin placements from some of my other attachments.
I used the premade materials because it was easier and relatively inexpensive. I had the holes cut and brackets made in less than an hour. Then I hand mixed many many batches of concrete in a wheelbarrow using an assortment of leftover cement types I had laying around. I used gravel and sand from piles I had left from other projects too. The whole project was done and mess cleaned up by 11:00 a.m., and didn't cost much at all.
I almost forgot... If you use the factory hole in the stabilizer bar for the toplink like I did, it is too large for the head of a toplink pin. I add a washer to the pin so it doesn't slide through the hole.