Hi Sean
I've got the white lenses. It may be that I can screw them down into the bases a bit more. But because the lenses are plastic, I don't think they will take much force. I think the screws will start to chew up the plastic / thread etc.
Initially I thought some sealer might help. But of course, you've got to be able to change the bulb.
Basically the lens needs to be pulled in tighter against the rubber base, closing the gap between lens and base.
In my fault ridden parts ordering, one of the things that I doubled up on was side light lenses. Might be a silver lining.
Tim