There were several Escort MK3 1.6.

Carb engines with 65, 79 and 96 bhp
MFI engines with 90 (rare catalyst engine, only a handful were built) or 105 bhp
MFI RS1600i with 115 bhp
RS Turbo with 132 bhp.

All came with the same gearboxes like the MK2 Fiesta. So it's plug&play. Driveshafts also fit, but you should use the thicker driveshaft (the longer one) out of a MK2 XR2.

You also need the XR2 (cvh) engine mount, Fiesta MK2 CVH alternator mount, drivers side CVH front tie bar and the XR2 gearbox cradle with the engine lowering.

Carb'd engines are quite easy to install. A FI engine needs a lot more work with wiring, fuel tank etc.