the later lights with the twin head lamp blubs and the indicetors in one are not easy to do to a early td5 
but from what ive heard the tdi300 and the early td5 use the same headlamps 
so what will be involved in fitting them will be triming of the front wings 
some triming and drilling of the front pannel behind the head lamps
maybe even abit of triming of the grill 
som one has done it in the march lro  put them in a disco1 v8 looks good