Dontonka

Hello just when you think you know it all you are corrected. Just bought a CMMG Lower from rifflegear.com out of Fountain Valley, Republic of California, and they had their last Complete Lower for 308. I don't want to offend anyone to call it an AR-10. CMMG ingraved MK-3 next to #19###. They told me to only order an upper by DPMS? ????? Is this true? I have a Law Enforcement background & Grunt in USMC in early 90's. Is it a POS or can I fix it up? ???? Thanks Much Don W WPNS 3/9