Hello again, and once again thanks for all your invaluable help. I am sad to report that the brittle plastic gremlins have struck my project once again.
I've just come from measuring the fuel rails and fuel lines on my SVO, which is by no means trusted as stock. I measured the fuel rails between the main rail and any fitting flaring, and I hope that is the right place to measure them.
Here's what I got. My fuel rail has two lines, one is 3/8" and the other is 1/4". The nylon line that runs to both is the same size at 5/16"
So if that is right, than these should be reasonable replacement fittings?
http://www.dormanproducts.com/p-20639-800-085.aspx
http://www.dormanproducts.com/p-12456-800-083.aspx