Would be fixing into either four-foot thick stone or poured concrete, mind-boggglingly hard. Which it is depends on the precise spot chosen. Had 132 mph gales in 2005 in the Western Isles, 120+ mph at the Skye Bridge, but that’s on the sheltered side of the island and at low level. I’m on the Atlantic-facing side and 400 ft up, so about the most exposed site there is, so would definitely get worse winds that the western isles report which would be from a spot down at sea level. The most exposed spot in Skye, for my money, is Cille Mhoire up at the north western end of the Trondairnis peninsula (Anglicised pronunciation spelling "Trotternish").