Any tips with installing new steering box?

[chevymotocross]

I have an 87 swb 2wd. I've already jacked up the front and checked common things like tie rods, balljoints, idler arm, pitman arm, and wheel bearing play. The truck wanders unsafely at highway speeds. Not an alignment issue, it's an issue of a "light" feeling and just a bit of play, in the box itself. Everything else in the front end of the truck is solid. The wheel bearings do have some play, but isn't there suppose to be some play anyways? It's an even amount on both sides, but there is slight movement. Anyways, I got a remanufactured box for free from a buddy of mine who bought it at pepboys years ago and lost the receipt. It seems pretty straight-forward. I know I will need to rent a pitman puller. Is it hard to break the steering hoses lose? How do I know if the box is centered? Any other things to look at regarding the horrible wandering and loose feeling at highway speeds? I know I can adjust the box I have, but since I have a new one, I will just install it.