It makes more sense to switch solely to 07/02. You don't have to change your LLC. It's up to you. If you end up with pre-86 dealer samples, the LLC can continue to own them (along with anything else except post-86 MGs) even after it isn't a SOT or FFL anymore. You'll just have to maintain the LLC for as long as you want it to hold those items.
If you go with a sole proprietorship, then everything is in your name already.
I'm going with a sole P just so I don't have to mess with the LLC stuff every year once I retire (filing annual report, fees, etc.) Anyone in my family interested in possessing the guns independently can become an employee.
You'll have to Form 2 new MGs yourself to get them without a LE letter, or buy them from a Class I or II SOT who isn't renewing their SOT in June (and normally they charge a premium for such occasions, because they know some other SOTs cannot obtain law letters).