I am looking for a very flexable tubing for uniflow in 4 oz plastic R/C tank. I want something more flexable than today's average fuel line, even more flexable than the classic Prather fuel line (Yes, I understand there are two types of plastic tanks; the ones that are leaking & the ones that will leak) The plastic tanks many years ago came with a VERY flexable tubing that had to be changed at least yearly. The clunk moved around very freely. I am willing to change the tubing if needed.