These are the instructions I got from Rob at Needswings:

1. jack up back of car, or just reverse it up onto ramps
2. remove black plastic shield covering fuel pump/filter
3. remove oem filter/regulator, wear glasses as fuel will spray when you remove the first line
4. swap in new filter, line from pump goes to the filter in,
5. line from out on filter goes to the regulator in either 3 or 9 oclock position, flow can go either way
6. line that went to tank on oem filter goes to the bottom port on regulator
7. install gauge onto face of regulator, use Teflon tape or paste, I prefer paste
8. small vac line from oem filter goes to small port on top of new regulator
9. mount new regulator to underbody bolt with supplied aem bracket
10. zip tie up the excess lines to secure them
11. have buddy turn key to on position without starting car, while your underneath watch the pressure gauge and get the regulator to 58psi
12. start car and verify pressure setting while running, the car will chug a few times on initial start up while it purges out the air bubbles
13. check for leak, recheck for leaks, after test driving check for leaks again, once all leaks are tightened up put the plastic shield back under the car and enjoy.