Venting trunk mount battery?

My 300c has a vented battery in the trunk, I am sure it is easy enough to get one with a vent built into it.

Back in the day I put a metal battery box out of a mid 60's van in a whole I cut out of the floor behind the passenger rear wheel. The Box was a clam shell type so half of the battery was below the floor. Made venting real easy. :)