I concur that finding the letter is probably not going to happen. I am only missing the one letter so I will likely leave the others on - but if more start to come off then I will probably remove all of them and resort to just a final sticker.
I am not sure on the carb question - didn't take a detailed look at the carb. I am thinking just a 2 bbl, but not 100% sure. Did the Merc come with two different setups in the 5.0 for the Maxum line?