four nuts hold it on.

remove fuel pump relay, start car and wait until it dies (should be under 10 seconds).

Then try to start again for 2 seconds.

Then remove four nuts holding rail down.

then pull the injector out.

remove o rings, install new ones and insert the injector back in the rail, then bolt the rail down, reinstall the fuel pump relay, insert key then turn to "on" and inspect for leaks.

If it doesnt leak, start it and watch for leaks.

If it doesnt leak you're good.