A method for forming a light engine assembly includes the steps of injecting a light trough material into a mold, thereby forming a light trough including a trough body having an edge, and injecting a seal material into the mold, thereby forming a seal configured to bond with the edge of the trough body. The method further includes cooling one of the light trough material and the seal material to adhere the light trough material to the seal material, thereby forming a unitary light trough part, ejecting the light trough part, and coupling a lighting unit with the light trough part.