Lexus01, thanks for the advice and encouragement to be a little more bold with the taillight assembly. I applied the screwdriver solution you recommended and it popped right out. Changing the bulb was easy after that. However, it was not the gasket that was the sticking point. There are two plastic snap pins that seem to be used both as a guide for mounting the assembly and as part of the retention mechanism. It was these pins that I was fighting on my first unsuccesful try. They snap right back into place when remounting.
Thanks Again
NJRX300
P.S. ncmarine2001 it was a snap once you get beyond thinking you might break something. Just pry the assembly out of its two sockets. Good Luck!