I recently unearthed a set of Brazilian rosewood I had stashed away in the early 90's. I was going to build a J-200 with it, but on closer inspection, I realize I could easily make an 18 inch body. Is that too much of a good thing? Anyone have plans for a flat top steel string that large? The matching sides are 4-7/8" tapering to 3-7/8" (34" long). When I google !8" lower bout, I get a lot of discussions about arch tops which is expected, but little on flat tops. Suggestions?