Brazilian Dodge Dart 76 (similar to 69 usa)

"I´m avoiding cutting and welding it to the floor pan."

You don't have to cut the sub frame connector to the profile of the floor pan, just weld it to the floor pan if/wherever it makes contact. That will increase the overall strength of the uni body.

You should be able to mig weld stainless by the way. At least the stainless we have here is weldable with the same set up. Test out a small piece and see if it works.

Looking good as usual! :cheers: