the rear calipers changed in around 87, so bear that in mind. but as said 8v/16v ones are the same, its the age you gotta look out for. MK3 ones are a straight swap for the later MK2 calipers, MK4 will bolt up but you need conversion flexi hoses.
The early MK2 ones have the handbrake lever on the top, later have it underneath. The reason for the difference is the handbrake lever changed, the early one has a pin holding it to a bracket welded to the floorpan, the later one is held to the chassis with 2 nuts. Incidently the MK3 handbrake lever will fit a later MK2.