I am going to be buying new rear leaf springs for my 69 350 Convertible. It currently has 4 leaf spings on it now. I assume these are the original springs that came with the car and that 4 leaf are what i want when i order new. I do see there are 5 leaf as well and just want to make sure i order the right ones for my application. If someone could just confirm for me that would be great. Thanks.