I'm with Chris Drew. Replace the cables, clean all connections, and go from there. I chased a similar problem around (and still am) and ended up replacing everything, so start with the easy stuff. I think I have mine narrowed down to either the ignition switch is going bad, or I really need to get that alarm out of there and rewire it. It's a mess!
Good luck, and check your mail.
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Gunning for 12's!
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