Now that our power is back on, I thought I'd give the rest of the story.
We had our power go out for four days. Fortunately, I had just filled our three 100 pound tanks of LP as well as my two 30 pound tanks so, we had plenty.
Lost our power.... had my wifes niece here to visit. Good for us but, she's a special needs and wheelchair bound so coming to visit her Auntie and having no electricity for four days.....no running (nor walking

) water meant no cooked dinner....no showers.....no toilets since we're on a well.
Enter brother in law.... wearing his cape with the magic "S" on the front. He had a 10Kw diesel generator "just laying around" Darn thing was on I-beam skids and he had to fork truck it into his truck.
Came to the house, asking if I had any spare wire... well... just so happens, I have 60 or so feet of 8/3 wire (or something huge like that) that I used to run a 50 amp circuit to my garage distribution box!
Little of this....little of that.... yank a couple unused wires from the downstairs circuits....and viola....we were hobbling along with power!
I even had a 5-gallon can of diesel to keep things chugging along.
Brother in laws are great, so if you are a brother in law to someone, pat yourself on the back!
To the sink issue....
Put the trap back together. Never got to use that pro sized roto-rooter machine as I could never get the tip of it beyond the bend after the trap. Probably doing something wrong but, didn't want to force things and break the machine or the pipe, especially since I knew the cold was coming (this was prior to power going out)
Put everything back together, decided to wait a while and just stew on some options.
Several hours later (where did I read this above??!!!!!)
Several hours later, wife came down "I heard a glug....can I use the sink now?"
"No, don't do anything yet, I'm still trying to figure it out"
Long story short... seems that "glug" was significant as we tried the sink later and it's worked perfectly fine ever since.
She knocked out about 3 loads of dishes then wham, power went out for the 4 days.
Got generator hooked up and she finished dishes on outside power.
Learned what breakers we could leave on and what others we needed to dance back/forth
If we wanted water, we could leave water pump circuit on. If we wanted to heat water, we had to either turn pump off or, not flush/use anything that would start the pump.
Want to take a shower? Need pump on but, heater off.
The sink turned out to be a rather miserable kick start to a rather miserable week!
Told the wife, we need to get her niece some form of "camping trophy" since she lasted a week with us under some conditions of duress.