We went there 35 years ago, I arrived wearing shorts and tshirt and was told I had to be covered up, so borrowed a pair of jeans of a lad that was outside (he was changing back into shorts) and tied a tea towel to my head. Well worth looking like a total dag to see the amazing interior.
They won't allow photos or videos in there, or for that matter in many castles or cathedrals ... so you develop sneeky ways to video. Have to learn how to turn off the 'recording' light.