Fuel Line Fittings Question

the general idea of that fitting (a compression fitting) is fine
when I use them, I use a swagelock version
this has two ferrules instead of one and is rated much higher then your fuel system will produce

I actually used them on my brake system to splice in the line lock

having said all that, the ones is use are stainless
the one you posted is aluminum?

according to earls (not a company with a bad reputation) these will hold up to 250 PSI
you're running what, 7?