Is your Scala carb or fuel injection?
If carb you can blow down the fuel line either return or send and see which pipe petrol or air comes out of, this will not work on fuel injection cars.
The fuel lines near the tank are very similar looking have you mixed them up or not sure which metal pipe on the fuel sender/lift pump is which?
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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