[jimmontg]

OK Kyle, the micarta is a good idea. Leave that as is, but remove before doing any of the following.

I am a sheetmetal mechanic and tig welder-fitter. What to do about the bow on the ends is simply clamp them in a vise square and right at the bow and take a rubber mallet and hit them until you get a flat surface. That is what I would do, I'm an expert at moving metal to where I want it.

If you do not have the confidence to straighten the platen out then simply use some high temp JB Weld and mix some non-wood grinding dust (fine) in with it and tape the sides and fill the area from the ceramic to the platen. Do one side at a time, wait until it sets and do the other side. Use a thin piece of plastic or metal to shove the JB Weld down in there. The reason for the grinding dust mixed in is so when the JB Weld Hardens it doesn't shrink much and pull on the ceramic plate which I am sure doesn't have much flexibility.

Any questions? I presume you are screwing the micarta on?