Has anyone imported (hauled) a dirt bike from Mexico to Texas?

I have an xr400r 2003 non running condition in Mexico...with a mexican bill of sale from dealership back from 2003...I want to bring it dissasambled inside my car...in couple of trips if necessary...i asked border patrol and one said i needed to fill an EPA form of some sort... and another one said I didnt need any paperwork just cross it in the car in non running condition....so who to trust? I dont want to risk it unecessarily...has anyone done this before? Thanks beforehand hopefully this post can help someone in the future...