There was a bit of a to do on this subject a while back, in the posh lads bit down the very bottom of the page.
Mine was down as 3050kg on the log book, so I sent the log book back to the DVLC to have it altered to the weight quoted on landrovers web site, can't remember what it is without digging the log book out, but according to Haynes the 90 pickup weighs 1661kg. I didn't have any problems from DVLC and sent it registered post.
So any old how when I took it for it's MOT the examiner queried the weight, and according to his wall chart for braking effort (the 90 wasn't on it) the weight I had given for my 90 was greater than the weight for a disco.
When he put the braking effort and the vehicle weight I had given him into the DVLC website for the MOT It came up as a fail. The nearest weight for the braking effort came out as 1200kg.
Before my next MOT I intend to take the vehicle to a weighbridge to find out exactly what it weighs, and have the log book altered accordingly.