Sibling Issues

So here's the problem...
I have 2 boys...1 with Asperger's and 1 without. The youngest models his brother's behavior, or lack thereof. As a result, I have 2 boys that no matter what I try, lack in social skills, especially with each other!
I am already sick of the tattling, the fighting, the "I hate you", "No, I hate you more!"
I have tried a multitude of solutions...none of which have worked for MY boys. I'm at the end of my rope.
A quick google search tells me I'm not alone in this problem.
Out of the multitude of suggestions, these are the ones I will be trying...

• Keep your kids safe...this is the first priority. My boys end to speak with their hands, rather than their mouths. So, I have to keep them safe!
• Acknowledge their feelings about each other. This can be done by simply saying, "So, you're saying that you are frustrated about your brother not playing with you. I understand that feeling." It's worth a try to get everyone calmed down, right?
• Separate the kids for a cooldown period. I usually do this anyway, and within no time, the boys are anxious to play with each other again. But after they've cooled down, it's important to bring them together to talk about what happened, and how to keep it from happening again.

Somethings I HAVE done...

• I have them say 3 things they like each other. It usually results in "He's cool, he's smart, and he's funny." Or something like that. But I keep hoping that at some point they will say more nice things about each other than mean things.
• I have them hug each other for 5 minutes. They hate this, being boys...but it usually gets them talking to each other again, even if it is about me!
• Occasionally, I have them write down what they did wrong, what they should have done and what they will do differently next time.

So what do you do when your kids are not getting along? Any tips? Because this might be a LONG summer if I don't get some peace in this house!!