If it is on a straight section of the tubing, you can do as is in this tread:
http://www.peachparts.com/shopforum/diesel-discussion/297198-look-what-my-po-did-transmission-cooler-line.html
I did the same thing on my W123. Make sure you use transmission cooler hose.
You have transmission hoses from the factory so using hose in another area should not be an issue.