The brass 90 degree fitting also from the RV store and keeps a short piece of hose from kinking.

For looks , I tried to keep the fitting in the center of the folds of the outside alunimum. Of course if you are keeping everything original, you might not want to do this. Just passing along some thoughts.

And, added by Nancy K., I was going to do this with my '69's rebuild, but then opted to not put water back into the trailer. I had purchased a space saving 6 gallon water jug at Walmart to use for my project.  It's turquoise!

From Gail & Jeff Fisk: We did not want to use the original water tank as it just looked gross so Jeff ran water lines to two plastic jugs under the sink, where the original heater had been. We don't use propane so we removed the heater but kept the access door to get to the plastic tanks. One is clean water and the one from the drain is obviously the gray water. If you go to the grocery store and get a 2 gallon container of water it fits perfectly next to a blue container you get in the camping dept of WalMart. They sit one in front of the other. I also bring my own water from home (in those collapsible jugs) in case I run out but only do this when we are on a week long trip. We added a sink in our Scotty bathroom, and it is plumbed the same way - two jugs. All you have to do is lift them out to empty or fill. We have used this procedure for two years and it works great. He also has plumbing to the faucet so that if we ever go to a campground with water we can use our white marine hose and not have to pump water. Another nice thing is I can see when they get a little funky looking and throw them away or in the case of the gray water jug, I can bleach it. We get a new one for clean water about three months plus it comes already filled.

Under the kitchen sink. Area is lined with rubber and there is a drain
in case anything leaks. Gray water jug not shown.

The bathroom sink

From Eric: I tried dreaming up lots of options on my 72 Highlander, I ended up just plumbing it with dual 2" PVC pipes, so it can hold about 2-3  gallons on the road, and I picked up a Thetford SmartTote tank to hook up while at the campgrounds. The clearance under the trailer just seemed too tight for a tank, and I wasn't about to chance puncturing a shallow one. (note from Len: 2" ID pvc will hold .1632 gal per foot. So a 5 gallon capacity would require 30' of pipe)

View of the rear valve 1"1/2 connection comes over from
the sink  "gray water" the double run allows for some temporary
storage while on the road.

From Don: I bought a large round oil change thingy that fits under the Scotty nicely.  However we have never used the sink (yet). I bought it at Advanced Auto, on sale.  Around $10 or less. It seals and you can pick it up and carry it away.  It is probably 30" in dia. and 4" deep, so it holds quite a lot.  It also has a pour cap.