Rear view.
I used 1-3/4" solid bar for the fulcrum ( I think that is what you call it) & 2" schedule 80 for all pipe. Installed grease zerts where needed. I wanted it to where I could remove the closing arms if needed to repair or just wanted them off. I first used 1/2" soft bolts for shear bolts, then #5, now on #8. So far have not sheared any #8 nor torn up any equipment because of them.