Great rickshaw, that's just what he needs. You can really see how heavy and well built they are. It's 1/4" steel I believe. That would be hard to work with on your own. I'm not sure it needs to be that heavy.
Also, he needs to know the size and thread pitch of the frame bolt. It would help if you could take one of the frame bolts to an auto or hardware store to get the size using that bolt size guage thing.
I see you got a second gen design because one of the upper corners is cut off at an angle. The first design with a 90 degree corner caused a problem with some Vehicri 'cuz the amount of weld bead on the frame varied and some of us could not get the bracket up far enough to line up the bolt hole. Some of us had to round it off with a grinder or jig saw or hack saw. Tone obviously took care of that at some point.
Mark