how do I....?

I was wondering, I seen the posts about removing door panel but I was wondering how do I remove the little panel under my back window. I have a 2 door 91 Z24 and I have a massive leak that fills up my back passenger floor.
I havent drove my car since it started to rain and someone told me to take that panel off to look for a leak. Does anyone know how to do this and what tools I will need?
Thank you for all your help as I couldnt find it in the search.

Better hope it doesn't look like this...
http://memimage.cardomain.net/member_images/7/web/811000-811999/811621_16_full.jpg
http://memimage.cardomain.net/member_images/7/web/811000-811999/811621_17_full.jpg

That's where the leak came from in my old 92 Z24

OMG! That's what my passenger side rear wheel-well looks like in my 92! Except I get a puddle in my front passenger side floor board, but I'm almost sure it's coming from the windshield seal-strip gap in the upper corners of the glass. Time for some silicon glue! As for the nasty hole in the trunk, duct-tape works well for temporarily keeping the water from slingin' off your wheel into the trunk, until I can afford a permanent fix, or the whole car rots to the ground, whichever comes first, with a kid on the way I'm afriad the latter.

time to get get some sheet metal then and fix that baby

time to get get some sheet metal then and fix that baby
LOL, I'm planning on it, I just need the resources, time, money, welder, etc.
I just can't believe, or can I, that someone else's is rusting in the same spot! Thanks for the design flaw GM!

time to get get some sheet metal then and fix that baby
I actually just sold it despite the whole "shock not mounting to anything" flaw to a guy for $400 from a local car club. He spent 2 days going nuts with welding and had it back up and running after that. It was his daily driver for a bit.