Drowned Pony Car

[jrfiller]

My daughter came home from college to inform me that while at Eastern Oregon University her 2003 V6 Pony Mustang Convertible became a bathtub. There was 2 inches of water in the rear floor boards and the trunk was full to the point the spare tire was completely underwater.
I have read several posts here and thought I might have figured it out but when I climbed under the car to find the drain hole in front of the rear tire I noticed the poly ground effects were blocking the holes. So do I drill through it or am I missing something?
What would cause the well to fill up completely? No leak around window either.
What would cause the trunk to fill up? Weather seal intact and in good condition.

I love this car and so does she but man this is ridiculous.

Any advice would be greatly appreciated.

 

[mransr]

The corners where the lower rear of the back window meets the fabric are prone to leaking, even when the area looks fine. The lower weather strip on the rear side windows can be a problem area too. But no clue how that water got in the trunk, even without the weather strip the inner lips should channel away the water.

 

[jrfiller]

Thanks for the reply. We are replacing the top, and I'm going to drill out the drain hole. If the top leaked and filled the well would that spill over into the trunk? Work in progress.

 

[mransr]

I think it would fill the back seat area way before the spare tire well...<shrug>