I went to work today attempting to dial in the tilting of the wheels. I triple checked the seating of the axle in the flanges and found that the axles were not fully seated. When I got them to seat fully they came out pretty darn square. I don't think I could have got that any closer if I tried. And that is from carefully laying out the holes in the flanges and drilling them carefully. The outer adjustable flanges were a different measurement to the height location of the holes because of how I layered the metal (1/4" metal inside the 2x angles). By getting those laid out correctly and center punched accurately the end result speaks for itself.
I used 2 aluminum plates to set my planes. One is on the frame and the other is flush against the tire. Ignore the bubble level. I was only checking the angle between the wheels and frame.
Here is a close up of how the flanges are on one side. I welded in the fixed flanges this evening.
Next up is the thread plates for the adjustable outer flanges. I am hoping to get to some of that tomorrow or over the weekend.