injector question.

[djssgsx]

stupid question i'm sure but i just need a quick answer before i fire my car tomorrow, how do i make sure my injecter is properly seated in the head? it feels loose.
thanks

 

[imagine-02]

I dont know if you can really check it with out the car running.
One of mine wasnt seated right when i switched my injectors and it made a high pitch whistle like noise.