Closed Back Combo's and Heat

Chicago Slim

First off, I'm a 6V6 guy. I'm used to the sound of vintage Fenders, and open backed amps. When Vox came out with the TB18C1, using two 6V6's, I thought that I would try it. I like the amp, it's sound is very Fender like, but the back is closed up. There are three 1/2" slits, along the bottom of the speaker, and three vents at the top. I live in the land of heat, sun and humidity. Not to mention salt air. I think that I may have to make a new back.

Is this enough airflow?

Doesn't this drastically reduce tube life?

Do AC15C1's and AC30C2's use the same configuration?

Do any of you remove the back panel?