on 30/31's or earlier cars with the 2 tooth steering box, the throw of the advance control rod is adjustable. Loosen the clamp at the top of the steering gear box that holds the column housing, loosen the clamp at the gas tank ( or from the bracket attached to the frame behind the dash panel on 31's) The column housing can now be rotated by gripping it at the top of the bottom support for both rods ( where they exit the column housing). Using the timing pin set on the TDC detent, retard the lever fully, rotate the column so the distributor arm is all the way back to retard in the slot of the distributor body. Check to see that full advance moves the arm forward to the full advance end of the same slot. When you have it right, tighten both column clamps, check to see the timing is correct, as someone might not have been able to fully retard it last time it was timed. Then, do not forget to replace the timing pin when finished..