A guy named John Cripes made a guitar for Jerry Garcia ,he had just made 1 guitar, he decided to make a guitar for his favorite guitarist, basically copying the Irwin that Garcia was playing, Cripes added some of his own features and came out with what was described as a guitar with massive sustain because of his neck thru body design and an unusual large volute at the Headstock of the neck.
Next, he found a way to get the guitar to Garcia, a couple of monthes passed and he got a call from John Macnally, publicist for the Dead, wanting to know more about the guitar, Garcia had actually already been playing it and was using it with the Jerry Garcia Band. Macnally ordered another one for Garcia and Cripes was paid $7,000 for the 2 guitars, unfortunately at this time, Garcia died. Ironically, Cripes also died soon after ,with an explosion in his shop where he made custom fireworks.(info from Relix mag.)