dedgin, I built a ripper 15 yrs ago somewhat like yours. Instead of building the 3 point hook-up on the ripper I built a trailer mover hitch before the ripper came to mind. So then I needed a root rake (as I call it) and put a solid piece of 2x2 into my hitch and welded a piece of 4" tubing crossways and cut the notches for the rippers to slide in just like on the box blade. I see where you cut pieces of pipe. I bent some U shaped bars to weld on my tube to hold the pins, again, just like on my BB. So after a couple hrs of pretty hard use, I realized my 1/4 in thick tubing was tearing in my notches. So, on the back side bottom and the top side front I welded some 1/2" X 1" flat bars to beef up the stress points in my tubing. No more stress problems. Over time the lynch pins would work their way out and I'd drop a ripper, never found 1 of them but to prevent that I took (4) 7/16" bolts and put 2 pieces of flat bar on top of my anvil and hit them (bolts) hard with a big wedge type hammer and put a slight banana bend in them and replaced my L shaped pins with banana shaped bolts. That allowed me to use them in the same U clamp holes but still get wrenches on them. I also used nylon style lock nuts, bolts don't tighten up but nuts do not work loose.
As far as the ripper causing problems on the tractor, on my TO35 Ferguson, I've never had a problem, it has done some pretty serious ripping. I had it on my 2200 Yanmar ripping out some small rotted stumps I had cut off at ground level with a chainsaw some 5 yrs prior. You could kick them out of the ground they were so rotted. I put on my root rake (ripper) and I was riding pretty fast, ripping stumps, using the speed and momentum, ripping stumps, never slowing down. I'd spot another one and as I started to cross over the stump I'd drop the rake and rip it, raise the rake and never slow down. Things were going good...until I hit one a lil bigger that hadn't rotted. Everything stopped, the tractor stopped dead in its tracks, but the big heavy plastic fan on my yanmar DID NOT stop. It rung the water pump shaft and my fan went through my radiator. 180.00 to rebuild my water pump and 200.00 to replace the radiator core.
So, I tell you all this to say do not get to riding too fast and dropping the rippers like I did. Learn from my mistake. Save your tractor. Ease up to it and drop the ripper and let the tractor PULL it out instead of RIPPING it out. It'll save ya some money.
We live and learn. I learned that lesson the hard way.
Your ripper looks good, I like it. After using it some, check your tubing where your rippers fit to see if your tubing is stressing, you may need to add the flatbar to strengthen your steel. And save yourself the trouble of looking for your ripper bars by using the bent bolts. Not sure if your cut pieces of pipe will hold up. There seems to be a good bit of pressure on the pins and it might tear your thinwall pipe out. If so, build the U shape loops out of heavier flat bar.
Building our own implements is a trial and error thing. You got it going on but might need to make a few adjustments/improvisions. It looks good, you'll get a lot of use out of that piece.
You'll want to build more attachments for your tractor and by building a 3ph trailer mover, you don't have to build the 3 ph part but 1 more time and it's easier to change out equipment pulling 1 pin and sliding a new piece in. I call it the reese hitch 1 pt fast hitch. (Farmall 140 1 point fast hitch)