I don't mean to stir up a problem, but I've painted several valve covers with great results. If you go to any autoparts store and get they're hight temperature engine enamel spray paint, this shouldn't take more than 3-4 hours tops. The link above is a good walkthrough. However wet sanding isn't necessary to achieve a nice smooth finish. One might also note that although getting the grime off the valve covers is helpful, it isn't necessary to spot clean them to perfection because they're going to be filthy as soon as you start sanding them down and scratching the red paint out of the letters and lines. I too used a flat head screw driver(as mentioned in the walkthrough) to remove the red paint. Also, make sure you sand every part of the outside of the valve covers. Where you don't sand is where the paint will either bubble up and try not to adhere, or later on down the road start peeling. After you finish sanding, then clean them with a rag or some compressed air... whatever works best for you.
The rest of this is totally opinionated(my opinion) but I'd use a high heat primer, high heat paint, and high heat clear coat(if you want them glossy). The thicker the paint and clear coat are, the less likely your going to scratch through the paint when reinstalling them. I've painted many valve covers and other "under the hood" items like this with no problems. Just make sure you sand well, apply several THIN coats of primer, paint, clear as opposed to caking the paint. If you cake the coats of paint on, it will be peeling back off in no time.
Have fun with it man. Post pics when you get them done. I'll post some pics of my Supra's valve covers when I get a chance.