Ditto on all the good advice, I've owned Summit, API and now a Timbertall Climbing Treestand and they all are great! Check out http://www.treestand.com they seem to be the online authority on treestands, parts, accessories and advice!
For all the effort and expense you have to go through to make one, why not buy a solidly built Gorilla 49 dollar loc on at Wally World????
Tell you a little story about homemade loc ons. A hunt club member of ours graciously offerred to supply a half dozen bowhunting loc ons one year. A month before the season there we were hanging stands. The member was trimming a few high limbs above the stand for head and bow clearance when all the sudden the platform gave way and he was left hanging from his safety harness.
Trouble was.......low grade bolt mixed into the high grade bolt bin. The bolt sheered off cleanly. Had he not been in safety gear, he would have fell 25 feet.
Wood stands.... Thats just plum crazy anymore given the excellent and affordable options out there.
Bring them in on a string. I love this term, if you want to be successful on calling in Elk, try not to just sound like the other caller. We all laugh at each other when we are practicing Elk calling at home or while camping. When I first started calling in Elk, I had no idea what i was doing and it's funny how many I could call in. The biggest Bull that I have called in to date was actually my first. I was making cow calls and screwing it up big time. But it's obvious I didn't screw up...