I used a wrench to do the job. Its kind of tricky to get into some of those places. They make an injector line removal wrench that you can buy through Impco. I dont remember how much it costs, but I did the job without one so it is possible. You will need an open sided wrench, just becarful to not over tighten them or to strip them.

I did not notice any improvement. There was some oil/junk, inside there that I cleaned out, but I cannot notice any difference.