I suggest that you find some experienced Amiga user that lives local to you to help you setup and get working all those good parts before you give up and sell it. It sounds like you would have a nice system that you would be happier with instead of just your other 040 A1200. If that can't be done, you will probably make more money selling the parts separately, but since you have not been able to get them to work together, you really cannot guarantee those parts and must sell them "as is" which will lower the prices you get for them. I hope you can find someone that can come help you put it all together properly. Find an Amiga club that is not too far from where you live. Even if you have to take the whole lot of parts on a long drive to have them set it up for you, it would be worth it.
Good luck!