help wiring loom install from 86 320i to 83 320i

[huggy]

Hi its huggy here can anyone please help me, you might of gathered im a net virgin but i need to know if i need an adaptor when installing an 1986 320i wiring loom in a 1983 320i the rest appears the same but there seems to be some sort of "plug" and as of yet i dont know if it will compatitable any comments or advice would be a godsend ta huggy you can also reply @ huggybear1872365@aol.com