I am sorry that you have been waiting for a response. I recently just logged onto the site and noted that your question hasn't yet been answered. I am a licensed veterinarian with over 25 years’ experience and would be happy to work with you if you are still needing assistance.
This definitely sounds like something that needs to be evaluated by a vet so that a proper diagnosis can be made and it can be appropriately treated. There are various dermatologic issues that can lead to itch and all are treated a little differently. He could have a bacterial or a yeast infection or the problems could be due to parasites like fleas or mites. In any case, with itching that bad, a short course of steroids will most likely be needed to break the itch cycle. If he will allow a bath, a cool water, epsom slat bath may help provide relief, but if he is not inclined to allow a bath, cool compresses may help until you can get him into the veterinarian. Keeping the area covered would help as well, but that can be tricky. Pet stores may ahve clothing or medical pet shirts that may work as a cone type collar probably won't do the trick. In a pinch, an athletic tube sock with the toes cut out and armholes cut in it may allow you to keep the neck covered.
As far as the eyes, it is best to keep any discharge from building up around his eyes by wiping gently with a warm water cloth. You can try flushing his eyes with eyewash or saline solution (like contact wearers use). He may also get some relief from an artificial tear type solution applied as frequently as needed to keep the eyes lubricated until you can have him examined. The product called Genteal® is available over the counter (OTC) as a solution or a gel.
I hope this is helpful. Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please reply so I can clarify for you.