Need help with 1986 WA Cuddy

[CDLongJr]

I have a box in the floor in front of the engines. I think it's a bait well. There's a pvc pipe in the stern of the box that looks like it has been broken off. There are no other holes in the box. I found a ball valve in the transom that drains, (fills ? ), the box. The po has installed a bilge pump with a hose to reach over the transom to pump the water out.
I'm trying to find out how the original plumbing was set up & tracker can't help. They referred me to you. We are restoring this boat & she's a real runner with twin 135 Mariners. Any help will be graetly appreciated.
E mail for photos of the box if that will help.