I have a 72-bass Hohner Concerto III S which is looking a lot lovelier since I fitted new straps today. However, the bass strap is a bit ropey, too, and I would love to replace it. I am amazed to find no guidance whatsoever on YouTube, etc, but expect there are very brainy people here who can help. Is it something that needs a professional repairer or could a banana-fingered newbie manage it without wrecking the instrument? Many thanks for any guidance.