A design for a new residential building at 140 Sixth Ave. features a lower, contextual side on Sullivan St. mirroring Soho’s historic architecture, and a taller modernistic, glass “mini-Lipstick Building” look on Sixth Ave. The project also will boast building-integrated photovoltaic collectors — or built-in solar panels — in its glass and balcony railings. The former gas station site just south of Spring St. needs a rezoning for residential use. Anthony Morali, the building’s architect, said a 100-foot height cap will be enacted with the rezoning, meaning the new building only could be about 10 stories at its highest point. There will also be a plaza as a “buffer” between the carwash to the south, he said. “We feel we’re in context with what the neighborhood would like to see,” Morali said of the design featuring two heights and two styles. The rezoning needs to go through the city’s uniform land-use review procedure, which could take more than six months.