I have a south bend 10 heavy the serial # stamped at the end close to the tail stock are 13281 RKX 16 . I know it is the 13281 thousand machine made , and the R = 10inch , the K = quick change gear box, the X= special , and then the 16. ,, Does any one know what the '' Special means '' and also what the 16 stands for ! I can't seam to find out the info on the two thing in the # .