Take a look at the DEPS here http://www.centralhobbies.com/contro...age/deps1.html, there's also a link to a how to article.

The same thing can be done with 4-40 steel pushrods instead of the carbon. I run dual pushrods, both in a straight line and solder them together on the servo end. There's a picture of one in post 11 on this thread http://www.rcuniverse.com/forum/m_76...tm.htm#7698989

If you have good straight runs and brace the guide tubes at several points they will be frictionless and have no flex.

Dave