I thought I'd finish this thread off, as I undoubtedly had to fill up. I took this pic of my speedo just as I had pulled into the fuel garage...

Not quite the elusive 600, but nor was it completely empty. I've never pushed the fuel tank to its limit, and I'm not going to, as I don't want issues with my car. I am confident in saying that I'm certain it would have gone to 560 (if cruising and not driving like a mad man

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For anyone wondering the set up: 115PD engine (not mapped), piper cross panel filter with smoothed box, milltech decat, and milltech resonated R32 style exhaust
