My old cookbox was slightly warped, I asked, took pics, received cookbox. I wasNO, if it is a new cook box, just install it as is. The coating weber uses is much better than HH grill paint. 15 years down the road, then, yah, maybe you will want to repaint it.
Why did they send you a new cook box?
Grill is holding up very well. Did a good cleaning last summer and I noticed cookbox.Good for Weber. Not bad for a grill almost 20 years old. How is the rest of the grill holding up?