A-Body Frame Rail Connector

while they may look clean installed think about it you are using a relatively weak floor as your top portion of your box, so you have a thicker U then a weak floor.......... I would use a nice thick wall box and make them yourself. Thought they are a lot better then nothing.

Hi!
I hope I understand your question, I welded some brackets on the floor before closing the boxes as the photo with stainless steel plates about 1 / 16 thick.