Fuel Injector installation tips?

[wc701lists at bellsouth.net]

Hey Guys...

Been years sine I've messed with Nissan fuel injectors, but planning to 
help a bud' with a replacement job.

I forget how I installed them into the rail in the past.  Are you 
supposed to use any sort of lube on them?  Or just use the caps & screws 
to force them in?  I guess wetting it with gas would be the safe bet, 
but unsure if more is needed.

-Thanks, Wayne Cox