First off, WELCOME to Team Crownline.
Not sure on the dying issue. Is this a carburated or fuel injected engine package?
On the fuel level, before messing with it, I'd run it a little longer. What you may find is that the gauge may go suddenly from full to about 1/2 tank once it starts coming down and that after that, it may show pretty accurate. Mine too will show full forever. But, when coming off plane after an hour or more of running, I'll see the needle start to move. Once it does, it'll drop to 1/2 pretty quickly and is accurate at 1/2 all the way to empty. The most accurate reading once your needle starts dropping is usually when you're at idle and not up on plane.
O'
"Little Mascara 3"
2003 266BR,496 MAG w/Bravo III