As one can see, this battery has seen better days. Most of that mess came from the baking soda I poured over it to clear out the caked up corrosion underneath.
Negative terminal is borked.
Positive terminal isn't much better. Going to need to replace the terminals at least. Maybe the whole harness.
Battery tray is a mess. Some of that is baking soda, some just rust. The hold down is a joke. Rock the battery enough and It'll slide right out. I need to replace it with a proper tie down.
Anyhoo, hooked it up to my charger, voltage across the terminals was 9V. 12+ hours later its back up to 12V. Was worried it was past saving. Granted I do want to replace it with an AGM one, but no rush. Given the damage to the battery terminals, I need replace that part of the harness first.
Cleaned up and back in. Fastest start up I've ever seen.