just bought a 1979 mercury 150hp v6 on a boat and trailer. the trim pump is missing and ive never seen one like what it needs. im used to the ones with 4 lines coming out of the cylinders that hook up to the pump. This style only has two lines, one from each cylinder.... Could I use a 4 line pump and plug 2 lines? What pump am I looking for? thanks. ser # is 5129871