We've determined we have the same tank, but my overflow assembly does not look like your picture. I did a web search to try to find the 'exploded view' diagram of my installation but could not find it.
The overflow "drain" on mine begins (at the tank bottom) with the bulk head fitting. Into this fitting goes the PVC tube. I wrapped the bottom of the pvc tubing with some teflon tape, just to make it fit snug. At the top of this PVC tube is an elbow fitting assembly (multiple parts). This fitting assembly includes a strainer cage. Essentially the opening in the elbow where the water flows in, points DOWN, toward the bottom of the tank. It makes very little noise.
The return piping again begins at the bottom of the tank with the bulkead fittings. The smaller PVC tube fits into the bulk head. I again wrapped the end of this tube with teflon tape to make it snug fitting. At the top of this tube is a 90 degree elbow that has an anti-siphon hole, then the flexible pipe mechanism that hangs on the overflow chamber.
When I get home, I'll look for the diagram that came with my kit. If I can find it, I'll scan it and post to this thread tomorrow.
I was worried about the return piping coming loose as everything was just dry-fit, but I have had no problems at all yet.
HTH