it looks like some of your wires were labeled! that a great thing. you just have to take your time and start from one end. or leave it alone.
dude just start over. if you post up all your gauges, accessories, bilge pump, etc we can make you a wiring diagram and simplify eveeerrything. more importantly it will be safe and reliable.
yah trailers are real fun! the best thing you can do with a trailer is have a batt there and just go at it!