The 3B (hard to tell if it is a 3B) has a fiberglass 3A tub.
https://www.facebook.com/marketplace/item/290336601626440
“2 Willys Jeeps for sale. This is a project that I would love to finish, but I’m moving and the cost to move them would be more than they are worth. The Jeeps are a CJ-2A and CJ 3B I believe as far as the motor transmission and transfer case go. I have a frame in good condition with title. My plan was to take parts from both of these to make one Jeep. The black one ran and drove when I got it, but the fuel pump dumped fuel all over the place. The fuel pump and starter were removed for repair and never put back on. The green one started, but would only run for a few seconds before shutting off. Both jeeps will need to be towed. I prefer to sell them together and with the frame.”