23.93 “minor change” is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product" and anything else is a major change.
A major change requires an STC (per 21.113)
The installation of a GPS would seem to be minor. So, why do they all have STCs? Even a Rosen sun visor has an STC. How can that be considered a major change?
A major change requires an STC (per 21.113)
The installation of a GPS would seem to be minor. So, why do they all have STCs? Even a Rosen sun visor has an STC. How can that be considered a major change?