So my pursuit into getting a mk5 Escort is not going to well if im honest, so im just wondering. How hard is it to convert MK6 and MK5B taillights into MK5A taillights?

Also i dont mind MK5B headlights as they are pretty much detangoed MK5A headlights am i right? But how would you convert MK6 headlights to mk5a or even mk5b headlights?