I have owned older vehicles but this is my first Jaguar. I purchased a 83 XJ6 with low mileage a week ago. It's been garage kept for the past 13 years. After a trip of 40 miles, I discovered dampness under the driver's side floor mat. Since it hasn't been driven in the rain, I'm assuming the heater core is leaking. When I contacted a Jag dealer, they said it would take approx. 20 hrs to replace. Another dealer says only 9 1/2 hrs of labor is required. I'm not sure which one is right. Is there anything else that may cause this dampness problem?

Thanks, BWL