From one wagoon to another, congratulations on the purchase!
I have two 69 B-Body wagons.
The first is my cruiser, a 1969 Plymouth Satellite 6 passenger 318/904 car from VA that I drove up to MA in May of 2014.
Here she is a few days after driving up:
And as of October, 2014:
I have done a ton of work to the car and am currently having the tailgate rust repaired due to a lack of time to do my own work. Before it comes out for the 2015 season it will be getting a front disc swap, new front and rear sway bars, and with any luck, rebuilt front suspension components.
I did a lot of gas-tank related work to the car and can tell you with certainty the following things:
1) The gas tank is identical to the 66-67 B-Bodies. 2) The tank filler tube seal that Rick Ehrenberg sells on E-Bay will work on the tank, even though the parts catalog (and hence E-Booger himself) say otherwise.
I also have the first wagon I bought in 2013, a 1969 Coronet Deluxe 6 passenger 318/904 basketcase, which I just had to save from the scrapyard.
Now it's basically a parts car due to extensive rot of all kinds, but I still like looking at it!
I have learned a ton about these B-Body wagons and what is really unique on them and what is not (but people just think is unique...), so I'll be following along, hopefully helping when I can!
Feel free to PM me if you think I can help with something!