There are a few reasons the torque arm modifications became important for this set-up. One, originally the sub-frame mounted lower because of the body disc spacers. Those were removed to gain more ground and motor clearance. And that left an awkward mounting location and spacing against the body. Two, the torque arm mount had a plate style mount to the sub-frame that required 4 1/4" bolts to be tightened from inside the frame. I was planning to cover those access holes up after the frame was welded back together.
The above is the original configuration. I needed more ground clearance and large exhaust cut-outs in the cross braces for Dave's set-up. And with the new transmission brace, I had planned on joining the 2 braces together... which allowed me more freedom to move the torque arm brace backward more and closer to the torque arm pivot point. By removing the cantilevered leverage and the ability to connect the 2 braces netted a much stronger and versatile core that each piece could be removed independently.