I had substantial water in the trunk when I picked up my S a month ago. One side drain was clogged, and the bumper vent does have a slow drip, and I found the DIY's for those.

There is an additional leak above the trunk, around where (I think) the trailing edge of the soft top meets the rear tray, if I read the anatomy right. Here you can see a discolored (wet) spot on the insulation where the water enters, and a puddle below. Does anyone know of existing detailed info and/or DIY for this?

 

Deep in this thread: https://www.s2ki.com/s2000/topic/465...trunk-picsfix/

...I found a link to this thead: https://www.s2ki.com/s2000/topic/872649-leak-in-boot/

which details fixes for a leaky rain rail.

I took apart the rear tray, discovering a brutal butcher job from when the soft top was replaced during an earlier owner's tenure. The nuts holding the rain rail onto the car were loose; I tightened those down, and did a quick splash test -- I think that solved the problem!

Now, to order replacement parts for those trashed by the soft top installers

 

I have a similar leak. I decided to just save myself the headache of chasing down the leak and just save up to get a hardtop.