Confident in the viability of his innovation, Dr. Bishop approached major automobile manufacturers in the USA and Europe, even setting up an R&D laboratory in Detroit, Michigan, the center of the automotive industry in the USA. Despite these efforts the inventor was unsuccessful and returned to Australia to further refine his invention. Additional R&D paid off, as after Dr. Bishop perfected his variable ratio rack-and-pinion power steering innovation domestic and international automobile manufactures soon employed it in a number of vehicles for the Australian market.