I recently purchased Dragon Kit 6016 (1/35 German self-propelled gun crew) and it contains photo-etched parts. There are no instructions pertaining to the parts and I have no idea where they are to be placed.
My experience with Dragon’s PE parts is that they are called in the instructions- you have to look carefully, as DML packs a lot if seemingly unrelated stuff into the various build steps. Often times the PE is for alternate parts, like the vehicle tools with or without molded-on clamps. Look around to see if there are small build sequences off to the sides of the main steps, generally labeled ‘MA’.