I am installing a 200 amp subpanel in a newly constructed outbuilding. I have two 200 amp main disconnects in the basement of my house. One feeds a subpanel for the house and the other I will use for the outbuilding. I have run 4 insulated conductors (L1, L2, N and EGC) in 2" PVC. N and EGC will be bonded at main disconnect only (N, EGC, main case and GEC), GEC will run to grounding rod. N will be isolated in subpanel and EGC will be bonded to subpanel case and GEC, GEC will run to grounding rod. Is this set up correct? The outbuilding is a pole barn, wood frame with steel roof and sides. Should I bond the steel siding to the GEC from the subpanel to the grounding rod? Thanks for any advice.