Akebono brakes cannot be rebuilt?

I wouldn't take the calipers apart unless you see some leaking, or want to change the o-rings between the 2 halves. To freshen them up. Just replace the pistons, seals and duct covers.

BUT if you want to get adventurous.

This is what I do with putting the halves back together. I use HI-Spot bluing compound. This stuff shows the high spots between the 2 halve. Put a small amount on a piece of paper towel. Wipe it across one half. Putting a VERY thin coat down. Bolt the halves together. Torque to spec. Then unbolt it. Look at the half that didn't have the bluing compound on it. It should have the bluing on it. Good mating should show about 95% to 100% contact transfer of the bluing compound. Where there is no bluing, is a low spot. To fix that. Use a honing stone and lots of WD40 to stone the halves. You will have to repeat the process several times to get it right. The last couple of calipers I did. After checking the contact one time. Everything was good.