[rheavn]

Unless some one has a better way to taper the tubing, I'm thinking that a better way to go is to adapt the 3/8" id black hose to a 1/2" id hose using an adapter. Then the tubing would fit into the 1/2' id hose. Would require two extra clamps, but this line is not under pressure.

This adapter should work----
http://www.oreillyauto.com/site/c/detail...&ppt=C0108