Water leaks

I know Skyliners are leakers, but how much should they leak? I'm currently restoring the interior of my '57 and have the seats out and the floor bare. I've replaced all the weather striping on the top and done a water test. What concerns me is the amount of water I see coming in from around the rear quarter windows. I realize that with only fuzzy strips at the base of the window, some water will get inside the fender and hopefully drain out through the drain holes. However, before I install my new inside panels, I would like to minimize the risk of these panels getting soaked. I will be installing the plastic sheath between the panel and the body. I was also thinking of spraying the underside of the panels with some kind of water repellent to keep them from absorbing moisture. Anybody have a similar experience?

I have put Dynamat sound dampening material on the sides and doors and it does the same job as the vapor barrier that came on the car from the factory. I have been told by a few people they spray a water repellent on the inside of the panels so it sounds as if your on the right path. Regardless - you need to put something there. I was talking to a man who built his car in the factory that he then purchased at a dealership brand new - He said they leaked all over on day 1.