Sid,
If you would like to improve the look of your Class J, I would suggest that you first darken the ends of those axles. Next, brighten up the number plate bezels the five strips on the front of the skyline casing and the handrail stanchions with some silver/chrome paint. One thing too note in the photo below. You will see a brass colored builder's plate. It also should be silver, along with the class plate that you may have on the side of the cylinder chest.
Later, if you happen to be picky, try to find a Lionel trailing truck. I am pretty sure that the one provided by Williams has a brake cylinder mounted on the outside of the truck frame. The J's did not have these.
