OK. What are you harvesting BTW, if you don't mind me asking? Down here in the mid-south US, cotton picking is about to wrap up. Corn and early soybeans were a couple of months ago, as I recall. Wheat beans, planted after winter wheat if grown, are about ready. Those are the big 3. Vardaman, Ms, which calls itself the "Sweet Potato Capitol of the World", is about 50 miles south of my Ms place. About a month ago when I was down there, I saw a bus loaded with what I suspected was workers. A few days later I saw a truck loaded with sweet potatoes in crates, headed for Vardaman I'd guess. Support Ms, eat more yams! Now back to business; I'm surprised you've dedicated this much effort to this.
I don't know what information is available on the Canadian site. There is a BT750C version for the B20 (as well as 2 versions of the -B, if you weren't aware). The -C appears to be a -B without the auto return. That's where I got the section prices I posted earlier, BTW. So, theoretically, we're converting your -B to a -C; although I haven't compared any part numbers and have no way to know for sure if they're interchangeable. With that said, I'm going to use the BT750C parts figure to explain the linkage needed.
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Heck, this is almost too easy. You'll need to duplicate, mirrored, part 010 to be like 020. Weld that peg on the side, I think you stated you're a welder. Instead of a groove to hold a cir-clip, I'd just drill it for a cotter pin. The rod end 060 is less than $20 from Kubota, so I'd use it. Rod 2, 090, is $75!, and won't work with the tang valve anyway. I think that the threads in 060 are 3/8"-24. Buy a 3/8" NF bolt, cut the head off to the appropriate length, cut a notch to straddle the tang, and drill a hole for the pin 110. Round the end of the bolt so it can swivel around the tang without binding. If you're feeling flush, you can buy 110 from Kubota for $12+ ea. I see screws and nuts on some of your sections. I drilled cotter pin holes in a nail for mine.
If you use a section with a clevis, you'll need to cut/grind the end into a tang instead of a fork.
