Mesa 50 Caliber reverb wire

[laptop44]

Hello I had taken the chassis out to clean the pots and find why I had weak reverb. I found a 2" white wire dangling from the end of the reverb tank. It looks like a ground wire from what I have seen in other Caliber plus pics. I hope someone has the same head .50 Caliber with EL84 (not the plus) and provide a pic to fix it


Thanks