Hello good people I have a 1967 cutlass I plan to put a 350 turbo and I dont know which cable length to go with, the 27 1/2 or the 30 inch. I see the 30 is for the dual gate shifter. I dont have that trans. Would the 27 1/2 be what I need? I am asking because the parts dealer thought the 27 1/2 would be short. I am guessing because the 350 turbo didnt come in the 1967 cutlass.