Using Unused Fuses Through Factory Harness Pigtail 2018 Raptor

[Coastal]

I'm trying to add an additional USB charger with more wattage (2.4-3.0) to my 2018 F150 Raptor and need constant, switched and ground. I've identified a couple unused fuses that go to the harness (like in this video:

) - 5, 28 or 29 for constant; 37 for ignition switched. I just can't find anything to identify which pins / slots in the connector go to which fuses and what the appropriate factory Ford probes/pins with pigtails (part numbers or descriptions from https://www.fordservicecontent.com/p...orcatalog.pdf?) I should get. Does anyone have experience with this or what service manual can give me this information (hopefully without spending a ton)?