Did John Wayne write inspiring letter to Montana school?

According to the story, "The Duke" once provided a classroom with a projector, several of his films and a $500 check.
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"He was trying to get his life off the ground, and he's handed this $100,000 check." The story of the unknown musician who helped Axl Rose write a Guns N' Roses classic

Axl Rose's integrity stunned an old friend who played a part in Guns N' Roses' early days ...