thats about all you need.
the standard ae86 brakes arent tooo much of an upgrade for ke70, but it does allow you to upgrade them easily (either to the jap vented disc, or to the other various upgrades, RX7/wilwood etc)
btw steering nuckels are the same as steering arms.
if they are the xt130 arms, they are a tad longer than the standard 86/70 arms. so you will get a bit of static camber with them.
your current brake lines will work with the 86 calipers, as will your tie rod ends.
you may require longer rack ends if you want to use the xt130 arms (i belive RA40 is the pick, someone someone may need to confirm)