Hi Roger
Many thanks, thought that might be the case there are some rebates on both sides and think bottom also on the inside of the cover. The guy who had the van before looks like he tapped the gauge because he thought it wasn't working so the battery level gauge has fallen back inside the void as it was held in place by sticky pad only, it was the battery that was duff not the gauge Didn't want to force that cover off unless it is supposed to come off.
Cheers