Converting an automatic 74 Swinger to a 4 speed

AJ, I have a quick question. With the TKX transmission, you have that to cut the upper structure of the torsion bar cross member. I have seen and spoken to people who haven't welded in a new upper structure. They just use and rely on the supplied lower bolt-in cross member. Would this be a problem? I too am looking to convert from auto to manual. Thanks in advance.
I've got about 200 miles on my TKX swap. The upper torsion bar cross member was cut without any additional bracing except for the bolt in cross member. So far so good. I do have subframe connectors to help stiffen the whole car. My Torsion bars are stock 318 bars and I'm running a 340 with aluminum heads, fiberglass fenders and hood. 18" wheels. 3:23 gears. I was running down the interstate today at 80mph, turning about 2000 rpms.