I've been struggling with making a Fat Rap-type lure, too.
I use 1/8" lexan for the bill. I bend mine cold in a vise. It is tough stuff, and doesn't break easily, but it will hold a shape once bent.
After I've bent the bill, I cover the bill with blue painters masking tape and then glue a small cylinder onto the top center of the front of the lip, using crazy glue. I turn it over and glue two more small cylinders onto the outside edges of the bill. Then I put the tip of the bill with the cylinders on it into a vise with wood jaws. I clamp it down slowly until I get the bend I want, plus a little to allow for spring back.
I use small cylindrical dropshot weights for the cylinders. They are about 1/8" diameter, and I find that is the right amount of bend when I close the vise completely. Plus the lead is soft, so it doesn't scar the lexan.
I am still struggling with finding a way to get the huge X action that the Fat Raps have.
I'm going to use Ben's idea of putting the ballast directly at the front hook hanger location, to see if that amplifies the X wiggle.
Why in the world did Rapala stop making them?