In the opening credits, the cash register shows $847.63 when Maggie is "scanned" (figure was taken from a survey (found by Matt Groening) done at the time that said that this was the average monthly cost of caring for a newborn baby - food, clothes, health, etc.). But during "The Simpsons" anniversary show (hosted by Troy McClure) the credit sequence is paused and the machine is shown to read "NRA 4EVER".
Grateful for your answers Boo deserved the stars for content and putting me out of my misery - that Q had been bugging me for years... Now go chase mice and ghosts