Front interior door lights off switch?

Hi all,

Is there a way of having the rear sliding door open without it switching on the front door interior lights (the ones in the driver/passenger doors)? Only had the van for a few weeks and I don't want to run the battery down while I'm camping with the sliding door open. Is there a switch i don't know about or do i need to wire one in?

Answers on a postcard to this address....

Cheers,

Rich