I use either Flite Metal or if subject is painted, 'needle files'. The chart tape is good but !

Try this - Get yourself a set of jewelers fine needle files, then first draw panel lines in pencil over primered surfaces, then using regular masking tape as guide run edge of needle file gently along masking tape for instant fuss free panel lines. There are a few different shaped files available experiment to create different width and shapeed panel joints. For raised panels eg access hatches use Flite Metal cut to size is my choice...

Cheers-