I'm refinishing a 23 year old Studio. 2 issues I'm facing are 1) there is a crack in the headstock, appears simple but I may have questions. 2) the flat black has gotten into the grain. I've sanded a little with 220 grit, any advice to get the rest of this off? I've lurked here off and on for years but the old threads I used to visit, the pics aren't available any more.