If you are new to the forum, then welcome.

First, the bump steer. You have a track bar drop bracket. You have two choices. First you can use a drop pitman arm that drops the same amount as the bracket. Second, you can raise the frame end of the track bar to the stock position. The idea is that the track bar and drag link need to be the same length and parallel.

Second, the castor may not be correct. You can get it checked at an alignment shop or get a simple angle finder at any good tool store and use the top of the steering ball joints for a reference. You need an angle of about 7 degrees toward the rear. This will straighten out your springs and prevent any death wobble in the future. You will need an upper or lower adjustable link to accomplish this.