replacing heater core

I'm replacing the heater core in my 96 sunfire and i'm running into a bit of a hassle. There is about 8 or so screws that you need to remove to get the cover all the way off. Well the last screw to remove is in the far back of the cover closest to the firewall. This screw has to be something that was put in before the dash was installed in the car b/c there is no way to get to it. There is about an inch between the screw and the floor and i can't get anything in there to remove it. I have tried to just pull it down as far as I can and managed to get the old one out, but now the new one won't go in at the right angle to get the pipes to go through the holes in the firewall. If anyone can give me any ideas of something new to try I would greatly appreciate it.

try a power screwdriver bit and turn it with a wrench that fits the hex end. That's how I did my cavalier. IT takes a while to get it out with the tiny turn you can get on it, but it worked

hi.sometime i find if u need to use a socket,simply grabing the socket withn rubber latex gloves u can turn it out by fingers.give it a try!

Well I got it yesterday...thanks for the posts though.