Neptune Optical Sensor Horizontal?

[dangles]

I'm wondering if it would work the same if I mounted it on the underside of the lid on a DIY skimmer cup overflow reservoir. I know they make skimmer overflow reservoirs but they are NOT cheap when I can repurpose a plastic container or something and just mount a level sensor in it to shut off the skimmer if it gets full.

 

[RoanokeReef]

The point on the sensor needs to be pointing up when horizontal not pointing down.