I found that using a piece of 3/8" plastic hose to listen with was very helpful. I put one end to my ear and pointed the other end at the area I wanted to listen to. I would bring it within an inch of the area. I found this to be extremely directional in nature.

1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed

My Chevy Master 4 Door is on the Road!