I had an alarm installed on the Tuscany we had. I went to a stereo shop that installs alarms. The shop installed a door switch, baggage door switches, generator access, and engine bay access. The alarm was not hooked to the ignition. We had a keyless remote that just enabled or disabled the system. Never had problems, not sure if it was worth the expense, but would probably do it again. If you go that route make sure the shop has a big enough place to park while they're doing the install.
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