OK...so made some improvements.
First, I added double layer red photo gels to the gun lights. Its easy to take them apart and access the hollow area, and cut out small circles to jam in there.
So now I went from this ->
to this ->
Still not perfectly red but...close enough.
I was also getting some light bleed on the bottom of the topper ->
So I did a quick and dirty fix, where I just taped a strip of black construction paper to the bottom to make a "skirt".
And had it flare out the front and two small pieces of tape to hold it down.
Completely not noticeable from the front...you can only see it from a step stool. Now no more light bleed!