Only wheelies backwards

lol hahahahahahahha, hi how are you, i did this years ago , if you look at the back of the truck . now stop and look at the diff case. the screws that hold it together.the head of the screw must be on the left side, even when you look at the front of the truck. turn it around look at the front of the truck, the head of the screw must be on the left . this happened to me when i bought my emaxx 2nd hand, my mate took it apart to clean it before i got it. and put it back together the wrong way around. we tried everything before we worked it out. what a nightmare, i wanted to stick pins in my eyes. if the diff screws are on the right side for some reason the truck will go faster in reverse. i kid you not. what a head fuck. i hope this is the remedy.