Might be that the fuel tank float has got stuck for some reason. If the guage goes up from 0 to quarter on turning the ignition, it sounds like the guage may be OK.
Depends on the tank set-up as to how easy it may be to remove the float - sometimes (but I don't know with the LDV) you can get to the tank and float from a cover in the 'boot' or 'loadspace' floor. If this is the case the job of checking may be fairly easy. In other cases it's a tank-off job - and a bit of a faff.
Is there anything in the tank which may have caused this eg Fuelsava device?
I would not recommend (but will write it so you can make you own choice) sticking a length of hosepipe down the filler and 'wriggling' to see if you could dislodge the 'sticking' - Do this at your own risk!
By the way, I have found replacement fuel senders to cost a packet so if you do need a replacement I'd see what the scrappies have.
J, January 2005