Generator Connection

I picked up a used 10kva (45a) Generac unit and want to get it connected thru the transfer switch. Just looking for some feedback on how to get it connected. I was going to use 1" schedule 40 indoors for runs of the 6-3 NM-B (about 75′ total) and four 14 ga THHN control wires in a separate 1/2" schedule 40, switching to schedule 80 before it goes outdoors. Then have a type LB on the exterior, then run the control wires directly to the generator and have the 6-3 going to a disconnect box. After the disconnect I was going to use either more schedule 80 or non-metallic flexible conduit with watertight connectors to the generator. As you can see, everything is above ground.

So my questions are:

• Use schedule 80 to the generator or the flex?
• Is NM-B OK in the conduit above ground?
• Where should the disconnect go?
• I had planned to bring the electric outside about 18" to the right of the gas going into the house. Is that OK to be behind the gas line attached to the brick?