Hello all,
Morning all, I have a 1989 FIrebird, 305, Vin Code E

How can I tell if my brake lines (going to combo valve) are M1.0 or M1.5, the tube size is 3/8"

Any information on how I can tell will be greatly appreciated, have been told that early 1989 had M1.0 and later 1989 had M1.5

Thanks in Advance

Brad