I've never swapped out the bills, but I have replace broken bills with similar bills on the DT series.
Be careful. The ballast is just below the bill, between it and the belly hook hanger.
I used a bandsaw to remove the broken part of the bill from the bait.
The bills have an integral post on the bottom half of the part that goes into the bait. When you have removed the flat part, you can pry the rounded post part up a little, and get some needlenose on it, so you can remove it, too.
A centerline on the replacement bill is the key to proper alignment. You can use the front and rear hook hangers as guides for the centerline of the bait, and line up the new bill to that centerline.
If you're careful removing the old bill, you can use the top of the slot that's left to keep the new bill square to the bait. Otherwise, you're stuck with trying to align it by eye, and wedging it in with toothpicks until the epoxy sets.
Good luck, and let us know how it works out.