Yeah, the ISO blocks are similar to SCART blocks, in that only half the pins are nailed down precisely, and the others are at manufacturer discretion. The most common ones to find mixed up at the connector blocks are the interrupt and the powered aerial. (pastel pink and pastel blue, both with white stripes)

Car wiring has always been entertaining. I don't know if they still do it, but in all the older Vauxhalls the positive leads were black and the grounds were brown. I thought that was a bit confusing... I set fire to a dashboard learning that one :)