The 383 pan I thought has scallops in it to avoid the steering linkage.

Now, I thought the 68 S/S had spacers on the K-member to frame? If so, at the same time did they move the motor away from the K-member (K-member to crank centerline distance)? If so, that might have gained steering linkage to oil pan clearance and you could used a B-body hemi oil pan.