The "+" are alignment markers used by l@sers during the etching/printing phase of the panel designs.
Normal stuff for CAD "Computer Assisted Drawings".
If so, wouldn't this process require more than one "+" per panel?
On all Boeing panels, the "+" does indeed align with the electrical contact. That is not to say that all panels have them.
Rgds.
NSEU
P.S. Tip: People casting aspersions on fellow PPRuNers' educations, should first check their spelling
