I’ve looked through the manual and finding conflicting info. I’ve put a rubber seal around end of jet pump like my 98 GTX, but it won’t allow the pump to fit into the pump shoe. So the manual shows putting a layer of “Great Stuff” to make a seal? One pic shows a neoprene gasket but I don’t find one to fit a 155 mm pump. It also shows using special washers for the 98 and 97.5 pumps on the gsx. Goes between the pump and pump shoe. Any help is appreciated.