Law is that they must be clearly visible during the daytime when activated and at nite when lights are off they must REFLECT back RED clearly.
Simple, if you modify from stock, which is DOT approved, then they are no longer DOT approved and would be ticketed at the discretion of the officer.
Returned 2006 Silver SRT8 (vanished into the unknown!)
2004 Jeep Grand Cherokee Overland
2009 Jeep Patriot Rocky Mountain
1982 Kawasaki KZ1100 Spectre