On my sedan you can lift up the carpet in the trunk to access a cover that lets you get a look from above at the gast tank and in-tank pump sender unit ect. On the wagon I don't know where this is. Check under the carpet in the back. I imagine that if you find this and remove the cover to access the 'knobbed circular thing' and start up the car you will be pleasantly suprised to find your outlets from the tank in a swiss cheese like state and leaking gasoline, which then runs along the fuell lines until it drops off to make a puddle on your garage floor.

This is what happened to me in any case. I took mine, the unit comes out of the tank (you have to message it out), to a local radiator shop and they patched it up for me for about 20 beans. 20k later and it is still togother. Have fun.

JS