Here's the chart for the Super Turbos. All of the single in/out Super Turbos will flow in either direction, but for an A-Body or B-Body you will enter next to the driveshaft on the offset, & come out for the tailpipe center.
Here's a pair of my chambered mufflers on a 68 B-Fish w/340: https://youtu.be/PdW5Vy1Dtv4 (I think it's one of our Moparts members' cars)