Another issue come up

[Mister 4x4]

Absolutely correct.  When I first got my tank, I was trying to figure out how to get the sender into that top venting port JTS was talking about, but my buddy reeled me back in and told me to look at the old tank.

The insert for the vent is also not reproduced [yet] so anybody considering getting a new tank might want to hang onto the old one until everything's back together.

Here's a shot of mine while I was putting the underside back together.  You can clearly see the sending unit poking out of the driver side (top of the pic):



Hope this helps!