Look up or keep your head level.
Body tends to follow the head. If you're looking down you're going to fuck up your form.
Your C spine doesn't need to be straight while lifting, very little of the strain is going to end up on it.
A lot of folks even argue that the T spine doesn't need to be straight while pulling (not as far as beginners are concerned).
Capt. Slow: Head up or eyes parallel with the ground.