Seconding John's review, this cage isn't quite a drop in replacement. I had to clearance a small nub of orange plastic directly behind the lower-front screw post. The cage didn't sit flush without it.
With the 41mm version, I also needed to clearance the white plastic directly above the top wheel (both sides), otherwise the wheel rubbed slightly. You could avoid that one with more crush; a 40mm version probably wouldn't need the minor Dremel action here, but definitely don't get 42-43.5mm versions. Maybe they work on the Rapid Red?
The cage was too short to flush mount with the stock barrel - about 5mm - but I had a parts-bin EAT with the same barrel (but longer) that I cut to size.
It was a little more work than I was expecting, but waiting anxiously for the final motors and Kepler wheels to put it all together!
The screw posts fit perfectly. A small section on the shell muzzle section needed to be trimmed. Also on the tighter spacing one of the holes on the shell for the motor shaft needed to be expanded. Also note the stock barrel is too short to fill between the cage and the muzzle. It does show off the wheels very well in the transparent section.