Correct. First came the horsecar streetcar, Manhattan's second, after the NY & Harlem on 4th Avenue and lower Park Avenue, ,then came the steam-operated elevated, then conversion of the horsecar line to cable. then cable to conduit electrification, then conversion of the steam elevated line to electricity, then rebuilding of the elevated with a continuous center track, then conversion of the streetcar to bus with tracks above 59th Street kept in service several months for use of the 65th Street shops for Queensboro Bridge cars and K and 125 X put-ins and pull-outs, then abandonment and removal of the elevated.
rc can more easily provide the exact dates.
Note correction to a previous post and insertion of the missing photo.