91 Accord tail light removal help please
 

I'm trying to change the gasket on the part of the taillight that goes
up with the trunk. The driver's side one leaks water into the trunk
after a rain. I open the trunk and water pours in from the light
assembly.

I got a replacement gasket, supposedly for that assembly, but I can't
get the part off. There seem to be four bolts inside the trunk that
hold it on, but removing those only loosens it, it seems like there is
a fifth bolt. I think I feel it, but it's blocked by the trunk metal
and I can't figure out how to get it off. I don't even think an offset
nut driver would get at that part.

Anyone know how to do this?