Threading dislocations are a feature of all current GaN-based power devices and are speculated to impact their performance and reliability. The aim of this study is to cross-correlate electrical and physical characterization of dislocations using electron beam induced current (EBIC), electron channeling contrast imaging (ECCI), and transmission electron microscopy (TEM) analysis techniques. Sample preparation steps such as deposition and etching of markers via focused electron beam (FEB) and focused ion beam (FIB) turned out to be decisive for successful characterization. We describe in detail various approaches required for successful cross-correlation and present appropriate workflows.