I got tired of my seat slipping and finally did something about it. Used what was recommended once before on here, but the pictures have since been taken off. So, I figure I'll put my version on here.
Using (4) 3" 5/8" mending brackets, (4) 4" 1/4-20 bolts (what I had on hand) (4) nylon lock nuts and some heat shrink to keep it from marring the frame too bad.
There really isn't much to this, I stacked 2 brackets on top of each other, heat shrinked them, ran the bolts through, heat shrinked them, then put 2 more heat shrinked brackets on the bottom of the frame, tighten down the nylon lock nuts.
The bolts aren't bent, just the brackets. I know how it looks though.
Any questions or want more pics, please ask.