The lines sold for 1963 & 64 Cadillacs are NOT good on all cars. Specifically, they do NOT fit Series 62 or 75 vehicles.
The lines they sell have threaded ends/screws on both ends. Refer to your shop manuals and you will see this is NOT the correct fitting for the transmission ends. A complicated setup involving beaded tube endings and sleeves with O-rings connected by rubber hose & clamps is required.
After two lengthly phone conversations with customer service it turns out nobody there knows this about the cars or their products. They are also unwilling to process satisfactory returns—you will still be out $45 shipping to you plus an additional $45 shipping to return them (!). $90 cash loss on your part for their error. I tried to post some of this info on their website but it turns out OPGI suppresses negative reviews of their products. So you won't see the heads up there.
For correct lines in stainless steel costing $20 less than OPGI, order from Inline tube in Shelby Township, Michigan. Here is link to CORRECT part: http://inlinetube.com/Preformed%20Lines/Web%20Line%20Listings/CA-CAT-04.htm