For the year of your Signature bass, there is no board that the pot mounts on. Here's a diagram of what you need to do when you get the replacement pot:
As you can see, they came off in order - so it should be easy to navigate.
The terminals of the pot are probably still on the end of the wires I have labelled. You should not have them in the wiring when you reattach the terminals.
Edwin will confirm with me tomorrow about the pan pot - I'll let you know.