You are correct in your understanding of the above.
The complete list of parts is
here, but the law lists 20 parts, not all of which are present on your rifle. The ones most commonly swapped out on an AK are the stock, pistol grip, handguard, gas piston, trigger, disconnector, hammer, magazine body, floorplate, and follower. The link I provided puts asterisks next to the parts on the MAK-90, but the MAK has no muzzle device, giving you 15 total parts.
The problem with using the magazine route to compliance is like I said- while it's very easy to do, you limit yourself to US made mags. The most common ones to swap are probably the furniture and fire control group- you can do all that work in less than an hour.