Grinding in Steering Column

I have an 87 S10, and whenever I turn the wheel to the left, I get a slight grinding noise coming from the steering column. When I turn to the right, the grinding is absolutely terrifying! Also when driving, the steering wheel likes to slightly lock up, easily unlocked by moving the wheel side to side.

I'm tearing the column apart this weekend to try to figure out what's wrong, but does anyone have any ideas where I should start looking?

Thx.