Set up a trust like "[your last name] NFA Trust" Use competent legal counsel that has done NFA trusts, Not your parents estate lawyer. Choose your upper but do not buy it. Determine OAL as if it sat on one of your lowers. Determine bbl length. Use the AFT website and file form 1 to transfer to your trust, pay the tax on line. No photo, no fingerprints. Use the sn of the lower you want to dedicate to an sbr. try to register in multi calibers. While waiting for approval, get lower marked with your trust name, city and state, ie., Smith NFA Trust, City, Mi. When form 1 approved purchase upper and assemble. Keep the Form 1 with the gun. At the same time, go to a class three and pick out a suppressor. Consider the sdn 6. Its for 308 but there is virtually no difference between it and a suppressor dedicated only for .223, Plus it gives you more versatility 7.62 NATO, 300 AAC, 6.8 SPC, 6.5, and 5.56mm NATO. Give Class three your trust, and he will take care of the paperwork and file to transfer to your trust on a form 4. Pay for suppressor and wait 8 months. When form 4 returned pick up suppressor, Keep paperwork with suppressor. Buy muzzle break.quick disconnect suppressor attachment from advanced armament. Put suppressor on . Next buy 300 blackout upper in same bbl length as original gun. swap out upper at range, When done return to original configuration. 2 guns, one suppressor, Twice the fun, half the price. I assume your wife knows all about this? Right?