99 TD5 with different battery tray??

Just picked up a battery from halfrauds (trade card so was cheap) got it home and it's the wrong size!

Anyone know if they changed the battery 1999-2000? Car was registered Dec 99 so I'm assuming it was the following model year.

I read a thread on here that mentioned the batt box was too narrow at the bottom for the battery. (Same problem)

wot is yo old battery? 075? 096?

or measure it.

No markings.....
But I will be doing some measuring of the old batt vs the batt for a 2001 disco