For fuel lines I started using teflon lined braided hose, although the biggest size I can get from Summit is -8. It takes a little bit of searching on their site to find the right fittings and lines, but its there. Doesn't cost much more really then the normal braided line. A little bit harder to assemble, and you can't get swivel fittings, but you can rotate the fittings up to a 1/2-3/4 turn with no leak worries, so you can still adjust them to the right angle. That's been my solution anyway, after trying to route some -10 aluminum line through a trans tunnel and make room for fittings so it could be disconnected.
Also, IMO, I wouldn't use aluminum for fuel line. Its just not robust enough. Yeah if you route it super carefully and fully support it, but any mistakes and that stuff can wear through or fatigue pretty quickly.
I'll never understand how you guys can grind down the welds and have no trace of the join. I've ground down nice small little TIG welds and you will always see the sanding/grinding marks on the finished product, not to mention the verysmall (.020) misalignment between two tubes that always creeps in. I'd really like to watch someone through that whole process sometime.