I got mk2. Think it's rev 3. 1996. Anyway. Put battery on trickle charge as it only gets used at weekends when it's dry, Took spare wheel out to get to battery, noticed just above battery on bulk head. 2 main rad pipes, then noticed 2 others. But there not connected to anything ? There in the middle off 2 main rad pipes or matrix pipes Help would be great explaining what there for. 