I have a Rogue RG-421-B 000 accoustic guitar in a black finish. I cannot tell if it is poly or lacquer. It will need at least some finish restoration/replacement around the bridge area. How can I find out what kind of finish this guitar had? Failing an easy answer to that, what is the best way to proceed with finishing an unknown topcoat? I have both instrument lacquer from StewMac and wipe on poly. I also have black wood filler from StewMac. Sorry if this is too vague.... I'm VERY new to this.