Hey there,
how are you,
Thank you for your support. I am currently working on my second book and it will feature the tank that you wanted to learn how to fold.
Till then you can learn how to make some of my other models thru my moneyfolders_unite group on yahoo and in my new book "Dollar Origami by Won Park" and also in John Montroll's book "Dollar Bill Origami".
In that book you can find my Butterfly,Dragonfly,and Eagle.
Won Park