I've never driven a 400 auto, but I spent a week driving a friends 400gt 5-speed around Northern California. It was heaven. The car is a great car to drive and makes awesome sounds. It seats 4 (sort of) and can swallow a weeks worth of luggage.
If not for the horrifyingly complex mechanical systems I'd have bought one. I also love the appearance. Go for it, but get the manual, don't attempt conversion.
Mark
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