Re: cheap steel?????
as far as petcocks go, i dont have one....the cheap one that came with the bike kit snapped on me when i was putting it on the tank....so luckily for me, I had a brass fitting that used to go to a cheap boost bottle kit i bought and it actually fit better than the petcock used to.....only bad thing is i dont have a fuel shutoff or any kind of screen in the tank. so i had to improvise a little fuel filter in the gas line from tank to carb as a "just in case" measure....anyways the point is you should be able to go down to a hardware store and buy a brass fitting to fit into the tank relatively cheap. be sure to teflon tape around the threads really good to get a leak proof seal, and for good measure JB weld around all of it for further leak proofiness.
Every problem can be solved with a conveniently placed brick.