You are asking a great deal and have not provided enough detail. The best thing you can do is to consult in person with an attorney who is familiar with business organizations and SSDI benefits. This simple Q&A forum is really no equipped to handle your matter. Good luck in your endeavors.
You need to see either a social security attorney or a tax attorney. Be careful, as you are proposing to defraud the US Govt. by making in excess of the limits without reporting such to the Government. You may be able to defer compensation if you are close to retirement age. Be careful and keep your comments off public forums.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
What you are talking about is fraud against the government, plain and simple. The system is not set up to award benefits to people who are making a "very good income." If you start earning income, you need to report it and will not be able to (legally) hide it via an LLC.