I dug up these JH quotes from an old thread:
johnhall wrote:There's three of these guitars, all of which I have. Two have finish on them, one only has a sealer. There are a few other small differences.
johnhall wrote:It's a different sound as they are wired in a full humbucking mode, i.e. the single coils are wired to work together in humbucking mode. They do less of the jangle and have more of a growl. Also, the neck shape is quite different, clubby by my taste, but what Jackson and Scott Thurston wanted.
There is also a photo of one of them on page 62 of the Bacon and Day book, according to the thread.