Tremec TKX first cuts

It takes 1/2 solid stock to be as rigid as what's cut out. It's inefficient but compact and easy to bend. You just have to watch how it ties into the lighter material. Otherwise you need to use material like the ToddRon cross member that is like an H beam or square tubing where you have lighter material with more vertical height.
I like the hooker cross member idea. But it bothers me that the trans mount goes to the inside of the upper half. I think. If the transmission mount bolted to the outside. You could drill some holes to the upper half and plug weld them to the torsion bar cross member grind flush. And the transmission mount would bolt over the outside. Plus instead of notching the top for clearance you could shift the upper portion away from the area it touches.
If I am wrong on this let me know as I have not had the parts in hand. Just that's how it looked to me.