Looks wild! Will soak up the big bumps now. It is a bit of a scary place to weld, in case of a breakage. At least that end of the A arm is not taking most of the weight, only the twisting and braking loads. A plug in the center of the tube helps to strengthen the weld. I've lengthened truck tie bars (for a lift) by sleeving a tube over the bar and welding into a couple drilled holes in the tube.
My son is working on a similar project right now on his Banshee.
Not a lot of encouragement on that forum...
Steve