Unless you have something I dont have it is a peice of cake- socket and a u-joint adapter was all I needed right in from the top. The wires were the toughest part to get off the plugs from all the heat. I would definately lube them up before you put them back on.
01 Silverado 5.3L 4X4
01 Camaro SS LS1 SLP
70 Nova SS 350
Already at 100K on an 05? Save your money on wires, not a common failure item on these engines. However, i would ohm them. I wouldnt replace them unless 1 is open. Open plugwires can still fire but the spark has to jump an extra gap.
Unless you are at 100,000 or have a problem then don't bother with plugs and wires. They are designed to go 100,000 before replacement.
I have 85,000 on my 03 suburban and have never touched the plugs or wires. Not planning to until 100,000 either.
I was told, have not done it myself, but if you put the vehicle on jack stands and then remove the front wheels, you can remove the, I don't know what the official name is but it is the inner wheel well covering that is held by plastic type holders, you remove it and you can access the last spark plug a lot easier. Never tried it. just a suggestion.