Oil Filler Tube Question

[cericd]

My 1970 C/10 has a 307 and I recently added front disc brakes with a booster. I had planned on using one of the factory oil fill extension tubes to make adding oil easier so I picked one up here on the forum. It came with the factory correct bolt but I'm not sure how to attach it. Also, it looks like I need a different valve cover for the driver's side of the engine. Mine has sort of a slotted hole for the oil fill cap but I believe the engines with the oil fill tube have a smooth circular hole to accept the rubber grommet that the tube plugs into.

Could someone post a pic of how the factory mounting bolt attaches to the intake manifold and how it holds the tube brace?

Also, is there a way to determine exactly what valve cover I need for the driver's side of the engine so I can use the oil fill extension?

Here is a picture of what I have (minus the grommet that plugs into the valve cover) and a close-up pic of the mounting bolt.