I am not a marine mechanic, but, if you crack open your carb and you don't have a kit handy, if there is a gasket on your carb when you pull the top off, the gasket may be damaged in the process. If your gonna take the time to do what your gonna do i suggest just buying a kit, might as well. My only experience has been with the mercarb so thats what im basing my thoughts from.
Good luck