As far as we know the Sonar (aka Spyder) and KS (Anzo) brand tail lights on our website are all street legal as mandated by federal law in the United States. This basically means that they are designed to the specifications set forth by the DOT (United States Department of Transportation). Occasionally, DOT might test models for compliance. If any Ford F450 taillights fail (rare) DOT will have the companies issue a recall. For those tail lens, you can return them to us for a refund. For any other brands besides Sonar (aka Spyder) and KS (aka Anzo), we can not guarantee DOT compliance. Also, please be advised that your local laws that may disallow these sorts of taillights to be used.
While smoking your Ford F450 taillights (tinting them) is certainly possible through the use of carefully applied spray tint (use light even coats), doing so may make them too dark to be legal. Please check your local laws as well as smoked Ford F450 taillights of any darkness might be illegal in your area.