Never mind being late for WWII...remind them of the USS Reuben James.
Remember the saying...."The Yanks, over paid, over sexed, and over here....
finish the saying for them....The Brits, under paid, under sexed, and under Eisenhower!
Best bet....be yourself....enjoy the evening...enjoy the fun! As you already note...it is a moment in history...it is an honor to be a part of it. If you pour half the drink you are provided into the flower pot...you might just remember part of it.