twisted minis
+1y
Since you asked I will point out the things I would do differently. Normally I don't like to point out flaws anymore because people seem to think I'm being a dick.
One, the bushing on top of the pumpkin would be better off with a rod end or pivot joint of some kind. You will wear out the bushings, and also the threads on that stud pretty fast if you hit sides. I learned the hard way with my truck. My threads got seized from it moving back and forth too much and working the jam nut loose. Now it wears the bushing out faster. Now I run rod ends on every setup like that.
Second, the gusset that goes in between the tubes that will be above your drive line is actually a stress riser at this point. The bottom being flat like that will actually cause more stress than needed in the area when ti tries to flex, and can tear the tubing. It is better for that flat area to have a radius to it so that it is rounded. Round edges hold a load better and will actually flex less. And speed holes never hurt anything.
Thats all I can pick out. And out of an entire backhalf I can only pick out two small things I don't like, you've done well.