I like the screw tabs on your step downs.
So what I am trying to do is create a oversize seam notch for REC./RAD. ELL'S, Offsets, Etc. So that when I run the oversize TDC seam you can then turn the piece 90 degree's and run the TDC connector without running over the oversize TDC seam that I just ran. After machining we screw the oversized seam together instead of a standing seam. Since it is not a fold notch don't know how to get it to notch up into the part correctly and then have it still notch the male seam correctly.