AN Fittings????

Zombie. Im guessing the -6an and -8an is confusing you. -6 is about the size of 3/8" line -8 is about 1/2"

Your cell has -8 fittings in the sump. You'll want to get a -8 to -6 fitting. run -6 to your filter and pump then run the 3/8 aluminum line to the carb.
Check out the kits that summit sells. They come with a bunch of fittings.