Yes, you get the full travel of the gauge when a) ignition is off or b) cables are disconnected at the sender end.
And it's been working fine for 3 years since the build.
Thanks mintcherrie.
I've re-read the second post but as I say, it can't be the float as I can move the lever up n down and the gauge isn't following properly
Sender seems fine on the bench with an ohmmeter- but dashboard gauge moves between 3/4 full and full- nothing less. Anybody got a gem of wisdom for me?