Not a clue
Have you ever read a post and had not the faintest idea of what the guy's talking about? "Hole Punched" the longeron, why would he do that. Nothing is prepunched on the -3. What the heck does 1-3/?? mean??? I can put multiple question marks in too!
So then I read Ironflight's response and the light comes on. Duh!
I'm sure glad I'm not building today.