Hi, the finish on the Yammies from memory were a satin black lacquer, not hard if you have a high pressure spray gun. Failing that you can buy satin black lacquer in a spray can. Start by rubbing the surface with oo steel wool to a smooth even surface then remove any greese and oils . Mask of the area and apply two light coats a few minutes in between each coat. Leave a few hours to cure out and rub with steel wool until smooth. Repaeat with 2 or 3 light coats and your done. the steel wool is used as it creates an even abraided surface to the bottom of the wood grain. If you try to put on too much lacqeur air bubbles will be trapped from the lower grain and will fail to work through the finish before it cures. The flattening agent wont be apparent for maybe a few hours after spraying so I quess you have to wait to see the finish blends. It wouldn't suprise me if you end up respaying the whole speaker when you get going, it not that hard it's just work and patience. I spent 35 years of my life refinishing furniture and building speakers for myself and comercially, something I really loved doing. Be also aware there is no such thing as black, most blacks ar dark dark blue or dark dark red. the dark dark blue would best blend with the Yammies. I hope this helps, good luck but you won't need it.
