What size are the threads for the tranny cooler in the radiator. My car came with -6 braided stainless tranny lines installed, but whoever did the conversion used all kinds of crazy fittings to connect the lines to the radiator & some of the fittings have a reduced ID & I'm sure that they restrict the fluid flow. I'm trying to figure out what size fittings I need to go from the tranny cooler in the radiator to a -6an line? I thought it was 5/16" to -6, but those didn't fit.