(Edit: looking back on my post I realize that I omitted the very important reference to Clay's guide that I was following. So with that in mind here's it is: http://www.pinrepair.com/clear/)
Today was Black Rose Clearcoat day. This is my first attempt at clear coating, and my low-cost fixer-upper Black Rose was the lucky candidate. While I would have loved to spray clear it, I just don't have the facility. And if as I progress I don't think I can get decent results I'll be sanding it down a bit and having it sprayed for final clearing. Anyhoo - here's how step 1 went. As I write the garage STINKS, and I'm going to stay clear of it for hours.
So first-off, the candidate playfield. I don't believe it was Diamond-plated, but it was fully mylar covered. With that in mind I didn't want to do any wood repairs and heavy sanding until I had some clear on it. So as of this point it was already stripped of parts, shooter lane restored, and the ball damaged areas near the cannon, Davey's Locker entrance, and center cannon shot have been prepped (rasp and file the rough damage and loose wood fibers out). I sanded the whole playfield with an RO sander on low with 600 grit paper, and cleaned all the bulb and switch holes.
So here's the candidate playfield prepped for coat: