Yep, fully agree with cerealsurfer to the letter! Where you live you'll be able to get a stainless tank fabricated for a lot less than mulfab and that's without the cost of sending it. Try a local car specialist or two they will either make their own of buy them in made to spec. the sort that look after weekend racing guys should be the first port of call.
Tank resolution methods are really only ever going to be a temporary fix and with problems in the future to revisit.
