Short answer.
You can put it on without taking the rail off, but you'll be a sorry, mad person when your done.
pop the rails and it will take you about 15mins. (including removeing the fuel rails)
If your doing this to get more fuel into the motor however, this will not do the trick. You have to reprogram to set the injector pulses or go bigger injectors to shorten the duty cycles. Your car will figure out what you did and lower the pressure back to OEM.
Not hard to install, and you can add it to your mod list, but questionable value. Oh, yeah, I got one too
.
Rob
