Run the car for a battery or two, then check the hub bearings. Mine freed up significantly, and now there's a bit of play that wasn't there before. It doesn't seem to hurt anything, but I'd rather not have the additional play. I thought about using some higher quality bearings, but I have other stuff to do first.
Side-to-side play in the steering block? Do you mean play that is parallel to the steering king pin axis (I think of that as more up-and-down play, rather than side-to-side)? If so, then that seems to be fairly normal. Mine was the same way. It's too bad that AE didn't try to use some type of bearing in the caster block. The steering rack is very well made and slop free. It would be nice if the caster blocks and steering knuckles were the same way.
Good luck with the build!
on page 10, top illustration where the steering block goes into the casing. From looking at the diagram, picture left to right, right to left movement. It's not exactly "free" movement, but it does move and the key bushing seems to have a role in this (as I tried it experimentally without the key bushing and a str8 screw in... then there was no movement at all. I didn't think that was right either.)
PS - the key bushing was a pain in the..... to line up.