Thanks Dave -- Glad to hear my fumbling around was actually helpful to someone. Sorry I didn't see your question in September -- it really is 6 large u-bolts that clamp the runners to the frame. Because the runners aren't as wide as the frame rails, there are spacers that ride inside of the u-bolts along the runners to make up the difference.
Yep, ole Blue has to go, along with 2 or three of the others. Too many "mouths" to "feed" around here.
John
