I did it afterwards, but then, My plane is 10 years old, has had one side of both wings sheared off in a story titled "Dead stick landing meets the Sapling" and numerous tails of landing gear being ripped off. But you can easily do a little surgery and (being a little more careful that I was) make some nice hatches to access everything. I took some pics last night to show you how mine is...

Here's the smoke pump under the tank compartment...

(Note the homemade restrictor valve that I made)