Splicing into existing wiring

[Sicktght311]

What are ya'll doing to splice into existing wiring to add lights, or anything outside of the cabin? I want to add another Perko light under my stern seating, and put a light on the swim platform, so i can easily splice into existing wiring in the transom locker. My concern is with the locker being a wet muggy area since its outside of the camper cover. For low voltage 12v, should i just snip, twist the 3 wires together, tin with solder, and then heat shrink to seal? I figure any mechanical connections such as T's, or crimps, would be prone to corrosion.

 

[firecadet613]

Snip and use an adhesive lined heat shrink butt splice to connect.

 

[Bill Curtis]

Or solder and use sealant lined shrink tubing

 

[Sicktght311]

Or solder and use sealant lined shrink tubing

Didnt realize that existed, and see they have sets available at harbor freight. Now i know where i'm going. Thanks