I wasn't going to reply ...because I'm not an expert.
Notable-Look at your intake valves and see the clean sides of them that's where the fuel is literally coming around the valve. So that's something to observe with the valve out BUT YOU NEED TO MARK IT AND THE CHAMBER which way it was facing exactly, WITH A LINE...so that it will seal again once re installed. The fuel likes that side. Check the stems for star looking wear patterns. Are they all looking like that on the cyl wall side. Etc