Redcharger, if you cut the connector to match the floor contour, you will be loosing a good deal of the structural rigidity that a box section gives. I understand if you don't want to cut the floorpan, as I don't want to touch my pans in my cuda either. another option is to let them hang just below the pan, and angle the rear up to the frame rail.

as for welding, a proper weld is stronger than the two metals it adjoins. the best way to weld sheet metal is to "stitch weld" it. this doesn't mean leaving spaces, but to weld an inch skip an inch and so on. then go back and weld the skipped areas. the other option is to do as stated above, spot weld (small weld puddles) down the length, then fill the whole seam in.

what car are you working on? we have quite a few pics of Rich's b-body if you want 'em.

Todd