We've been noticing that our main gear wheel farings are vibrating in cruise. We are not sure when this started (we've owned the airplane since June) or if it has always been present. Since buying the airplane we have removed the rubber tubing spacers and replaced them with washers (per advice here) and notched a semicircle into the bottom edge for access to the valve stems. Could the pants have become crooked or distorted during any of these modifications? Or is some vibration normal? We've got tundra tires, if that makes any difference. Thanks!