Spark Plug Replacement 2008 tundra 4.7l

first time replacing plugs 2008 4.7l v8 tundra, cannot get driver's 3rd plug have removed 3 bolts and in attached pic you can see what is in the way(some air valve?) it moves now but will not lift out and have removed 1 hose as well is there a trick? HELP don't want to apply too much force seems like it should come out easy appreciate any hints thanks.

 

Well after 4 hours i got the 4 plugs in on the drivers side but started getting eaten up by mosquitoes so will finish in the morning. I did find the following on another post quote: 'air pump for the emissions system. I have changed the plugs and it is a pain.
I carefully unbolted it from the engine and removed the aluminum tube connected to the bottom. Be careful not to lose the metal gasket between the aluminum tube and the pump. Simply remove the hose clamp and remove the rubber hose from the back. I did it this way and reused the metal gasket with no problems.' end quote... so that is what i am dealing with right now am stuck simply lining up that unit with the 3 bolts and the aluminum tube at the bottom will give it another try tomorrow it is a freaking PAIN in the you know what...

 

Denso Iridiums...
One and done; free HP with the change and they will last 100,000 miles.