If you use a 1 piece drive shaft, you will be just about at the limit for for a 1 piece shaft. You have to be very careful that the shop that builds it gets it true and balanced. 2 short shafts are much stronger than a single shaft. I am going to put a Saginaw/BW in a 50 model GMC. It will have a 302 engine and I am leaning toward 2 shafts because with the 4.57 rears and .70 OD, the shaft is really going to be spinning.
