'68 Mustang Won't Start

Sorry that the compression test turned out so poorly. You would need to replace the block at least. I wonder what you plan to do from here, that you want to pull the engine.
You have already checked the piston rings by checking the compression.
If the pistons have one cylinder at no compression and the others at low compression, you have to accept a general condition of engine failure and decide if this car is worth the expense of replacing the engine. The block is shot if there is reduced compression in some cylinders and no compression is one cylinder.
Unless you can find another very old 68 Ford 302 block in good condition, I think you need to give up on this car.

But that’s in the realm of just car repair. I suggest you look online for enthusiasts of this very flawed but certainly iconic car. You might find a buyer just for the remains of your car. Make sure whoever that might be pays all transportation costs and puts serious cash in your pocket, especially if the body is in good shape.