A livestock guardian is not really a crate dog
Great Pyrenees were bred to work independently, at night, in high country, guarding sheep from wolves. That's the temperament you get: independent, nocturnal, thick-coated, and philosophically opposed to being confined. Pyrs can be crate-trained, but they don't take to it as naturally as a retriever or a herding breed, and long crating is genuinely inappropriate for this breed's psychology.
The 48" or 54" crate is the correct size — most adults are 85–130 lb with substantial standing height. Heavy-gauge, wire, never covered. This is a breed that will lean on the crate walls and bend cheap ones.