I don't understand why you had to pry the con rod to get it off the pin, it should slide off the crank pin easily after you remove the cylinder liner from the case.

What is the condition of the liner? Did you check to see if it is still round? Is there an anti-rotation pin inside the piston ring groove that the ring is hung up on?

One more thing, are you installing the piston/ring from the bottom of the liner?