If your garage is getting to 50°C you've got a major insulation problem! Where are you located?
In both cases if min and max operating temperature are an issue it may be best to install in an FIP enclosure and use ducting to keep the enclosure and an optimal temperature.
In many houses, the garage is outside of the insulation; the garage itself has very little insulation between itself and the outdoors, and there's lots of insulation between the garage and the "habitable" parts of the house.
My garage door faces the southwest meaning it gets hit by the sun for a good chunk of the day. It easily gets to 120F during a Houston summer in there.
In both cases if min and max operating temperature are an issue it may be best to install in an FIP enclosure and use ducting to keep the enclosure and an optimal temperature.