What Tony said.
Gather your collection of photos, then examine your drawings, critically. Really critically.
Is that panel in the drawing too square compared to photos (being sure to compare like with like, i.e. they're both F-5E and the one's not an F-5A)?
What fasteners stand out? And how visible are the rivets anyway?
Some modelers do tend to go for the fully riveted look, which is more a matter of taste IMHO, and only a good option on natural metal schemes.
But if that's what you want, search for a cutaway drawing, such as Flight magazine or Aviagraphica in Aeroplane magazine used to provide, so that
you gain some understanding of the underlying structure before you have to resort to inevitable guesswork in some areas.
And welcome to the forums.