PIR Sensor mounting

A Sensorswitch PIR sensor (right) was purchased because (hopefully) it will provide years of service in the hot Florida sun.

It would be nice if could be installed in the Defiant (Home Depot) fixture (left): I do not have confidence in the Defiant brand fixture sensors lifespan. The problem is that the angle of the fixture is at 45 degrees and not 90. As I see it the options are:

• find another fixture
• find an adapter

Are there any other options that I have not considered? The constraint is that the Acuity sensor must be used in the design. Thanks!