Here is an easy mod on the DML Flak38(kit or pre-built). When I compared the DML Flak38 to pics of the real one I noticed the space between the "Y" base and the gun mount to be too wide, it should sit down flush on the "Y"base. Here is how I corrected the gun base.
Before the mod note the section between the rotating base and the "Y" base

I removed these tabs

Here is the "Y"base with the tabs removed

Here is the gun mount after removing the tabs
