Position of CO2 canister on tear shaped model?

[k18m]

Hey, I am currently designing a tear-shaped vehicle model (with the large part in front, small in back), and need to find the proper place to put a c02 canister. I am trying to figure out if raising the wheels off the ground, and placing the canister above the wheels, and below the point would be better than cutting a bit of the point off, and placing the c02 in there.

Thank you in advance!

If any more info is needed, I can give...