I do the same thing but I usually cut them in half before smoking. Takes up more real estate but it helps with the drying process. Japs take a long time in the dehydrator, but well worth the time.
I keep them whole, and set my UDS at about 150. I'll let it run for about 18 hours and then check.. They're usually just about done by then, but if not I'll just toss em in the oven at 200 and they finish in an hour or so.
@cheez, yea, for all practical purposes you could call them chipotles I guess. Just smoked dried jalapeños.