Originally Posted by mach4

I'm not familiar with the oil cooler setup on the 603s, so I don't know if my solution (custom 617 setup) might work in your case.

What I did was adapt aircraft style AN fittings and stainless braided oil lines for my cooler. Here's a link to the process

http://www.peachparts.com/shopforum/3048510-post118.html

It does require brazing and drilling/tapping, so it might be too complex.

The primary advantage to this solution is that the fittings are reusable so if you ever need to replace the lines again you can just make up a new line yourself and be ready to go.

Again, I just don't know whether this would be a potential solution in your case, but one never knows.