Remove mid top hexbolt on back. There are six long hex bolts on the bottom that connect to the lid. In mine, the lugs in the lid were a bit loose and one of them remained stuck on the bolt, nothing that i couldnt wriggle loose. lid lifts from back and hinges on front panel with two small tabs.
I see you call it AK4499EXEQ which is the name I see in the AKM product lineup on their website. Others just call is AK4499EX, which is not on their webpage. Are they one and the same?