Wiring a topper, and internal lights

Hey everyone, so I bought a Leer 100XR topper last week, which fits perfectly on my 2014 DCLB Tacoma (the topper came off the same type of Taco, different color).

The topper has the third light, an internal dome light, and an electric lock that can be tuned to my key fob.

I plan to eventually add internal LED lights to the inside of the topper to be on when the engine is off.

I've never done wiring before and have watched a YouTube video or two on this, but I wanted to ask you fine folks about any tips, tricks, or tutorials I should be looking at.

I am planning to solder the connections (not the first time for me, but it's been ... 15ish years) in order to create solid connections that will last.

Thanks! Pic for attention (plus ain't it pretty?).

 

Ignore the sloppy connections, but this thread has good info on wiring you shell:

https://www.tacomaworld.com/threads/camper-shell-wiring-step-by-step-picture-load-warning.279665/