I recently acquired a new-to-me Shen upright bass after playing electric only for about 20 years. I know I should take it to a pro to get it set up, but the closest guy to me is about 30 minutes away and I just don't havre a lot of time or occasion to make the trip. Mostly I just want to make sure the string height is ok, so I bought one of these tools from Amazon but I have no idea how to use it. Any ideas?