I just picked up a Royal B-17 that was started by someone that did not know what they were doing, I will be going electric, I'm finalizing my set up now.
I would highly recommend that you put the batteries in the fuselage, you will probably need a bunch of nose weight, it would be a shame to add a bunch of lead when you have those batteries. 2200mAh is not enough, you will want flight time, you need 5000mAh. Heavy outer wing panels will hurt the performance of the plane. You will hear a lot about keeping wires short, but I've not noticed problems with this. A guy on here built a 14ft Spruce Goose and he put all the batteries in the nose along with the ESC's! Those were some LONG wires!
I will be making my nose glass area removable, just dowel and magnets to hold it and the ESC's will be in the wing saddle area.
It's going to take some time for me to catch up with you, so I will watch your progress.
Luke