The most difficult problem in designing a solid body of the instrument was its design so that the 30m 2 stained glass window behind the Transfiguration stage was not covered. The main designer of the organ was Dariusz Zych. In March 2008 the assembly of organs in the cathedral was started. After completing the assembly work, the tuning process (organ intonation) took place for two months. The dedication of the organ and the name of John Paul II took place on June 15, 2008.