Hunter500ky

Hello everyone this is my first post and sadly its because I need help. I ordered a avic d2 from someone, it looks great but the av in out harness does not fit into the back of the HU.... I cant find one anywhere!!!! I have a 06 tacoma with the JBL system so I have to have thise hook up. Can anyoe help me? Point me in a good direction? Its clear the harness I have is physically to small to fit into the HU if it was like 2 rows bigger it would fit. Thanks in advance!!!!