Hell, sounds like given the right application could be a test bed for tubeless.
I just wonder if a narrow what is that 15mm wide band were cut from the old tube and glued directly over the spokes. I don't think that would be prohibitive to setting the bead would it.
I know the rim tape goes right under the bead on the MGB and it has no problem. I could definitely see against having that go up the wall, but to me it seems like a good application for making some DIY bands with the old tubes.
Maybe I'm just totally off base though.
