Looking back at DaveW's & Jimmyw's comments I too find that the BRBs are rubbing the tyres. This is on a 2013 4+4 with standard 165/80 tyres. After less than 1,000 miles both metal & rubber are shiny. The dealer who fitted them says that it's not unusual & nothing to worry about. But to me it's simply bad design & I'm tempted to remove them.
Forgive my ignorance but what are "chassis rollers"? - they don't sound like a standard Morgan part.