how do i remove the fuel line at the fuel rail?

the sping lock tool is easy to use. it slides over the fitting and the groove in the tool slides into the spring lock ( you will see the spring) when it's pushed in just pull the fuel line and it shou;d come right out.

if your taking your injectors out make sure you spray the o rings with some spray lube that will help the o rings slide into the bores
 
Any auto parts store has them. Get the cheap plastic ones (it's a kit with 6 or so small plastic disks) they are only about $6 to $10. Don't buy a fancy set for more, it's not worth it.

You need the tool for not only the gas line to the fuel rail but also your fuel filter.
 
Those plastic discs suck ass. I've broken a ton of those, bending the hell out of them trying to put pressure on them when it's at a hard angle.

Those O shaped ones with the spring in the middle are by far the most trustworthy and are like 12 bucks.