It is fitted with a good immobiliser, as part of the engine management.
The specialist insurers say theft and vandalism are very rare indeed. Is it that your insurer (not a Morgan specialist perhaps?) is insisting that an alarm be fitted? If you speak to someone like
http://www.moginsurance.com/you will find they don't expect an alarm, and the premiums are very reasonable, being based on classic car policies.
My only concern is leaving luggage in or on the car, as it would be very vulnerable.
