As a scortched surface can't be cleaned back to normal,try and you will wear hole in it and I can't come to your funeral I'm busy working on my Lunar Solar.
my idea would be to.
1 overlay with simlar patterned material
or
2 cover with thin plywood stained and varnished and as you have done reduce the wattage. Try even lower 20w get one see if light produced ok, that's what we use. I did this on mine cutting the ply shield shape, looked good.
bob
February 2011