Steve, you may know this so sorry if I am appearing pedantic. Let me share something Kirk Evans taught me to get perfect lines. Use green 3M tape and mask along either the top or bottom side of the line you wish to create. Then block sand to the tape. Prior to removing the tape, place another strip of tape kissing the first on the other side of the line. May or may not take multiple recoats of high build primer to get it where you want. You can lightly sand the top for a more muted effect or leave them like razors, which I did. Actually, the layer of paint and clear dulls them anyway.
Anyway, you probably want them to be consistent with the crispness of other lines on the car.
I had no idea that these lines were so easy to shift. I thought it necessary to work the metal underneath. Not so at all, the primer has enough thickness to shift them.
Make sure to put your decklid in place. Same technique will marry the line from the roof to the decklid perfectly.