I have used the cycle inner tube as well, works quite well but I don't ever leave it in there.
On a side note I have not done this on my PSD because it does not have a sliding glass, I do this with my 2000 yota TRD with ARE cap when camping.
On a side note I have not done this on my PSD because it does not have a sliding glass, I do this with my 2000 yota TRD with ARE cap when camping.