AuntyM, what is it about those things that makes me think of the Terminator? Looks like parts off an android!

I too, have an old Eastside. I didn't want to drill through the rails so we came up with a moveable contraption consisting of two metal plates, which are sandwiched around the rail with four wing nutted bolts. On the front plate we mounted a fish on rod holder mount. These are nice as you can move them anywhere you like.

Hope that helps.