Speaking from experience, 7 pin connectors are a nightmare whilst the 13 pin connectors work, every time. The 7-13 pin adapters introduce another point of failure so avoid.
As for light boards in general - I hate them. The ones you buy are fragile and prone too damage to easily.
I've just bought some LED lights from ebay with twin reverse and twin fogs. Will be getting some suitable board and making my own up.
Will also be fitting the light board with its own integral 13 pin male connector, allowing the long cable to be disconnected. I hate having a long cable permanently attached to the light board.
I also have a two A-Frame's on my trailer, and will be fitting lights to the top of the rear frame. I accept that they will not be legal on their own (too high), however, at least I will have some permanent lighting fitted for that short run when I cant be arsed to fit the light board or when the light board is broken for whatever reason.
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