During my Guildford days, we used sometimes to take the choir to St Peter's to give concerts. After the dry acoustics of Guildford, St Peter's was a real delight. The console - HNB - was dreadfully uncomfortable and the pedal board a horror. But it made a fine sound. The Swell, as I recall, was at the east end of the organ but the shutters when open would send the sound against the opposite wall and then down the Nave.
Very sorry to hear of Stuart Bellamy's death. But good to hear that the organ is still in one piece. I believe someone altered one of the mixtures - and removed the tierce. Grrr. But such things can easily be reinstated.
Acoustics at Guildford are hugely improved after removal of asbestos and I believe the organ has taken on a new lease of life, although I have not yet visited since the organ was renovated.