Mine came from South Africa and it looks a bit hand made, but is very solid - I guess you could get similar made there.I'm living in Brazil, I was looking for some other tanks, but there is not so much avail. There is a Aux-Tank which will be installed underneath the car, but I already have a Inox-Exhaust-System there.
The tank over the whole front seats would be cool, never saw this down here.
There is a original Version under the driver seat with 63L for the Bandeirantes after 93. But my '89 has there the Battery-Box.
I'm gonna think about it, let's see. On the other Hand: I have a canister on the rack in the back and place for another two in the car behind the rear-seats. And the cases, that I really run out of fuel are selden.
It's welded aluminium plate. I don't have a good photo, but this is what it looked like when I received it - its been cleaned, replumbed, and had a new sender fitted since then though!
If you go down that route then I'd add plenty of baffling inside - you don't need 100+kg of fuel sloshing around when you corner/brake.