help changing spark plugs yukon 04 slt

hi everyone i am trying to change the spark plugs and wires on my 2004 yukon slt, already reached 125000M (i know i am way overdue), this is my first time doing this so i have a few (maybe dumb) questions.

- Are the new ac delco spark plus already gapped? or what is the gapping on this truck?

-is there a distributor cap and rotor i need to change as well?

-i also want to change the pcv valve but i heard after 2004 these truck dont have one,its just a fixed orifice...is this right?

thanks in advance everyone.

If you get the proper platinums they should be gapped, if not the label under the hood should have the gap setting. This should be coil on plug ign. I do not believe there is a dist, look and see, rear of the engine as usual.

I atleast visually inspect all of them anyway, don't take it for granted. If there is any doubt they are easy to gap anyway. They do have short plug wires. The individual coils, one per cylinder are mounted on top of the valve covers. There is a wire down to the plugs...

thank you very much for all your input.
I guess the pre-gapped spark plugs are the iridiums, but i guess i will stick to the originals.

ooops i guess the originals on this truck are ac iridiums..

thank you very much for all your input.
I guess the pre-gapped spark plugs are the iridiums, but i guess i will stick to the originals.

ooops i guess the originals on this truck are ac iridiums..

most plugs you buy are real close anyway. The distributorless and coil on plug ignitions used now days can jump a gap upto like .090" and up. The set for most that is spec is 40 to 50 thousandths though. The new systems are capable of VERY high voltages. The main reason plug gaps are completely out of whack when they are is that they or their box was dropped....