Road Runner Nest

Approximately how long does it take gasoline to varnish?

My Road Runner has been sitting without running for at least a year. I plan to replace the carburetor and intake anyway; however, what steps can I do to ensure that I don't cause harm to my new carb?

My plan is:

Remove the gas tank and drain it, but how do I actually clean all the varnish out?

What about the gas lines from the tank to the carburetor? How do I clean those?

I was gonna just run the car for a little bit with the old carb until all the gas is sucked out of the lines, but didn't know if it was a bad idea.

My first runner sat for over a year and the carb varnished up but not the lines ,I added stabilizer to the remaining gas in the tank after i rebuilt the holley carb and it fired up,After that when I knew I wasnt going to use the car for a while I always added the fuel stabilizer and had no problems.I also remember adding a can of carb cleaner to the gas tank to.