rag-joint is on the left, u-joint is in the center, and coupler is on the right. Each are different lengths and widths. The coupler is the shortest, the U-joint is the longest, which all effects the mounting position of the steering column and pushes the column further up into the interior of the car. 65-66 has very little steering column (IDITIT) exposed in the engine compartment, and using a rag-joint or u-joint won't allow you to secure the bottom of the column to the firewall and leaves you a big hole. Somewhere on this board I saw a modification adding a tube sleeve to the lower mounting bracket that did a very nice job of sealing up the firewall and column and permit you to move the column farther into the interior.