Steering/Alignment Help Please

[C10_ustacould]

I am working on the truck formerly known as "Project Underhaulin" and I've run into a situation with the steering and alignment. After the alignment the steering is "twitchy" and the is a screeching noise when turning to the right, so I put it up on blocks to investigate. I shot more grease in all the zerk fittings to see if it would have a positive effect on the steering and the noise, unfortunately no change. But while I was checking the steering I noticed the wheel didn't turn the same amount in both directions. What I'm hoping to do is start fresh.

I figured I should share the truck's set up. It's lowered 4/6 with 2.5" spindles and 1.5" springs up front and 6" with springs in the rear. The front suspension uses '73 and up components. And the steering box is mounted with 3/8" spacers due to the '67 frame.

I took some measurements and noticed the for tie-rods were different lengths. The left side is 16 3/4" and the right is 16". Should the center link be centered in the frame?

So... I'm thinking I should center the steering gear and the center link and readjust the tie-rod ends to center it up and gain the correct toe. I'm also thinking of pulling all the shims in the upper control arms and having it put back on the alignment rack.

I'd really like to hear some advice from those of you with alignment experience. Thanks in advance.