Changing the O-rings for most Moen one-handle kitchen faucets can be done without doing anything below the sink except turning off the water at the supply line valves.
Remove the faucet handle. Most models have a screw behind a red/blue plug button or under the handle cap (go to Browse Products to assist in locating your model. The parts breakdown will show the location of the handle screw for your model). After the plug button or handle cap has been removed, use a 7/64" hex wrench to remove the handle screw. Follow the parts breakdown for the order of the handle mechanism. Once the handle mechanism kit is removed (including the spout retainer nut) rotate the spout back and forth while pulling up.
Some Moen faucets have handles that remove by loosening the screw in the back of the handle. To loosen this screw use a 3/32" hex wrench. After the handle has been removed unscrew the spout collar nut by turning counterclockwise then lift and rotate the spout.
Remove the existing O-rings from the valve body noting the location of each. Clean (with 50/50 solution of vinegar and water) the inside of the spout and the outside of the valve body. Lubricate the O-rings using the silicon grease included and install the new O-rings on the valve body. Apply the lubricant to the outside of the valve body and the inside of the spout hub.
A helpful hint:
Always lubricate faucet O-rings with silicone-based grease (Moen part number: 99915). Do not use plumber's grade faucet grease, silicon sprays or any lubricant that contain petroleum. Petroleum based lubricants may react with rubber seals and actually cause the faucet to become even more difficult to operate.
Re-install the spout, handle mechanism kit and the handle in the reverse order.