George,

Good pictures of your oil cooler and hot air exhaust outlet installation.
Just one more step and you will be finished with a more efficient operation.
Take a piece of light aluminum and make a rectangular shroud for the outlet
side of the oil cooler. You can form the outlet end to conform to the
cowling and put a piece of 1/4 inch foam on the edge to seal against the
lower cowling.  This will physically direct the hot air out the louvers and
prevent the hot air from turbulating inside the lower cowling area.

Bob Smiley
N94RJ