For the battery I recommend a lipo cell, at least 150mA.
I can't imagine what the problem with the reciever is ...
It seems that you have ordered the swinging rear axle from Peter. If you want to let it swing, remember to put as much weight as possible as low as possible. This is essential! But it will be anyway quiet difficult because of the epoxy chassis wich is much lighter than a brass frame.
With the chosen configuration the TTTT capabilities of the truck will be limited due to the tendancy to capsize earlyer than with a fixed rear axle.
My first truck was almost the same ... MAN 5to with the same parts from Peter.