So I want to get a pair of Sparco sprint seats. Do I need racing harnesses to use them? If I do need to use racing harnesses, how can I mount them SAFELY without the use of a rollbar? I have no problem with using a rollbar, but I'd like to have use of my backseats (to a certain extent). Also, the universal seat sliders from Sparco are $50 at most places, how will those install in my 95 RS? I doubt the holes line up for bolting it down.