Y cables are easy you can buy good quality cable (2 strand heater cable with a rubber outside) and cut off about 1/2 inch of the insulation and twist them together and either solder them or if that is scary try a marionette it looks like a pen top but has a metal insert inside and it just twists on the wire you will need 2 female ends and one male. I don't like marionettes that much myself but I solder a lot so it isn't a big deal for me. I'd use electrical tape over the marionette and wire leading to it.

These things...
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