Reva downloaded the navigation data right before leaving & has the map visible in her right eye as they travel. If someone has a device & wants a copy for their own sake (good idea!) it can probably be arranged by wireless transfer. And yeah, the idea is to dismount a couple kilometres or so from the derelict & go on foot from there. (GM: Does the buggy give off some passive signal of its own, or do we need to make a marker in order to find it later?)