I followed your steering wheel thread in the other forum but this is the first time I've seen the whole truck. You do beautiful work!
What turned you onto the Fiero fuel tanks? That is a very interesting setup. What is the total fuel capacity? Was the fab work on the fuel filler hoses difficult? How is the under the seat fuel filler working out? I'd be afraid of over filling the tank and spilling fuel all over the nice carpet. Have you had any issues with spilled fuel?
I may need a new tank in my 58 Suburban. Since nobody makes a replacement tank, this might be an option.