[ShrimpBurrito]

I have replaced the faucet in my 2720SL without removing either the water heater or water tank. It's not fun, requires a bit of contortionism, and a beer or two helps significantly. Be sure no young kids are around, as you will probably swear alot, too.

There are at least 3 ways to approach it, in addition to, as you said, removing the sink drain pipe:

1) You can loosen the sink hold-down clips with a very long flat bladed screwdriver such that you can lift the sink up an inch or two to get a wrench in to those supply lines. A mirror can help depending on where exactly they are located, but it's still painful. Reinstalling them is far more difficult, but you could save that part till you got home if you needed to.

2) You might be able to use a basin wrench to loosen them, too. Loosening supply lines is exactly what that tool is designed for, I just don't know if there's enough clearance in there to turn it.

3) You can cut the PEX supply lines (PVC pipe cutters work great), and then completely remove the sink using method #1 above to remove the nuts. To reinstall, provided you don't have a PEX crimping tool, you can use Shark Bite connectors (at Home Depot when I last checked a few years ago); one end slips right over the PEX, and the other end has a threaded connection to which you can attached a flexible braided standard supply line.

I ultimately did #3.

I can't remember if I looked into this, but when the bathroom walls are folded down, you do get some access to under the sink. Check out whether you can sneak something in to at least the hot water side of the faucet.

Dave