1994 C1500 350 Idle adjustment? Help???

[LoveTrain59]

Hi, I Have a 1994 c1500, with a 5.7 350 TBI. I decided to try to repair my head gasket, and mid way through was told by a mechanic that I should just put it back together before I mess it up, So I did.

Long story shot, I have it back together, and it runs and starts, but it idles at like 1500 RPM, and sounds way louder and different then it did before. There is one plug that I cant find where it goes to

Heres a pic of it: http://imgur.com/a/F4ExU

Any help would be amazing, Thanks.

I also accidentally adjusted my Kick down cable by screwing it a few times one way, So how would I adjust that to where it needs to be?

Thanks for any help.