Search:

Sure, you can lap them out. Used to be recommended, and I guess still is, to rub the plate down with a chisel or a plane blade. I use a 12" Stanley Hurwood screwdriver (the length, not the point)...

Same info, just busted it up with the 'enter' key to make it easier on the eyes.

The suehiro is a bear to lap. The Atoma 1200 is the best diamond plate there is IME, but pricey.

Try the unused...

At my house all synthetic hones that I've had, with the exception of the Nortons 4 & 8, will not remain flat between honing sessions, even if I were to flatten them at the end of the session....