Until you get a little further along with the project, a gas tank for an outboard boat motor makes a good substitute for the correct tank. One upside is that a plastic tank doesn't rust! Most boat tank fuel lines also include a squeeze bulb that comes in handy for priming a carburetor if it runs dry between work sessions.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!