Couple of things that made me suspect an air leakage
- The fuel filter was usually full of air (or vapour)
- A couple of occasions when accelerating hard the engine would lose power.
Checking the inlet and outlet fuel pipes at the fuel pump identified a poor looking pipe that had obviously been repaired (patched up in the past) – see pics. The tank inlet union was well corroded and was most likely the cause of the problem.
I bought a length of braided fuel pipe that would replace the older original pipework.
I drained a couple of gallons of fuel into a couple of containers then jacked up that side of the car to tilt the rest of the fuel away from where i was disconnecting the fuel line.