Boy oh boy. What a Pandora's Box..
To replace the damaged 10" horizontal pipe from elbow to elbow, I had to disconnect the kitchen faucet. What a challenge that was with wing-nut connections bunched up together with the sprayer hose. Once disconnected, there was no way to reconnect it. It was obvious to me, initial installation happened during assembly of the cabinet.
Here is the faucet as it was originally installed. It was a real struggle to disconnect the lines because the wing nuts interfered with adjacent pipes, and impossible to re-connect. They cannot be spread apart inside the cabinet because the PEX plumbing passes through a hole below (see picture in opening post), locking them bunched together. If disconnecting the PEX below to lift the faucet, the connections can't pass through the hole in the countertop because the wing nuts are too big.
Here was my solution, replacing the setup with flex lines that pass through the countertop hole (after minor filing of the hole to a slight elongation) and easily connect inside the cabinet.
The flex lines connect to the PEX pipes with these. Working the crimping tool inside the confining area was also a challenge I had to remove the black drain pipe to get the tool in there.
Cost was cheap. Though an opportunity for a faucet upgrade, my wife really likes the plain white single handle faucet with the sprayer.
If you have to disconnect your kitchen faucet for "Any" reason, you face some serious challenges.