How thick of metal for frame connectors

I'm not a real big fan of 1 x 3 rect tubing for this.

This is how I did mine. Got lazy and didn't fishplate at the torsion crossmember.





For my use I am going 1'' and 3'' wide so I can stay away from the floor boards and rear brake cable, my little 66 valiant will be getting a front sway bar and new rear spring this winter and I think it will be a good to go deal for me crackedback, I see Pettybluedart has the 1''X3'' on his race car and running mid 10'es 1/4 mile so they should be great for my /6 road car.
I want to thank you for the pictures, this will help :cheers: