[mloy]

The drawings I have state 17.5" center to center on the main tubes. This would translate to 14.5" measured between them.
I've heard different dimensions flying around everything from your stated 17", 17.25", 17.5", 17.125", etc. I went by what was written on the paper drawings I purchased as I've learned (don't ask me why) that they are more correct than I gave them credit for.

Hope this helps,

--Mark