What the other guys said.
To enhance your straps, simply get some foil, masking tape, etc and cover the painted part so you get a bit more depth. Maybe toss them in the bed of the truck.
About the shark mouth on the hood...IMHO, it detracts from the historical feel of the model and if there were one painted on, it would have pointed in the other direction. As it is, the open end of the mouth is to the back of the truck.
Try to find som ammo boxes for your guns. In combat, those two

guns will be dry very quickly and the gunner's going to want to be able to grab a new magazine right quick.