Just getting back into playing trumpet after 20 years...

I have always had the top of my lip showing above the mouthpiece when I play. Should I try to remedy this as I start over; or not worry about it?

It depends on how much it`s down. When I play, I can always see just a *tiny* bit of my lip above the mouthpiece. That`s ok. But pulling your mouthpiece down on your top lip is a problem that leads eventually to having to start all over with your embouchere.

A good test is to look in the mirror and set the mouthpiece on your lips like you were going to play, press down really hard, and pull it away. If the white line on your top lip is not at least 1/2 of the circle formed by the mouthpiece, it`s too low, and you should definitly try to pull it up.