Few questions by a clueless fella new to RC

[jarndice]

If your soon to arrive Heng Long Armour are the latest models they will have both I/R and BB capabilitys so no need for 2 Turrets as to BBs do not use the ones supplied with the Tank they are seamed and will damage the Airsoft seals in the Gun, BBs are readily available on E-Bay for very little money,
If you are worried about water getting into the electrics then where available get a metal hull and if a metal hull is not available Dremel out the battery box (There are lots of articles on how to do it within the Forum) then line the floor and inside walls of the Tank with Velcro,
Glue Velcro to the battery and place it high on the inside wall of the tank and glue velcro to the base of the control board and smoker and place them wherever you want in the Tank knowing they are secure and yet ready to be moved when you want to.
Remember it is your Tank so do not feel restricted in how you modify it/them any problems we are here 24/7 just ask.

[Herr Dr. Professor]

Taigen/Torro is dragging behind on the matter of BB and IR equipment, so jarndice offers an important qualifier that "your soon to arrive" Sturmgeschütz must be "Heng Long...latest models." I second jarndice's advice to get some good quality aftermarket BBs. Above all, it's good to hear from you again and learn that you are still actively RC tanking.