Couple of things to watch for that will make your swap a whole lot easier!
The bottom two bolts holding the fan on may be rusted, so have replacements ready. You might as well replace all four.
The radiator comes with the top rubber mounts where the bolts attach it to the body, but it does not come with the bottom mounts, you re-use them off your old one and the tiny thin e-clips holding this shaft to the radiator may be rusted, one of mine snapped. Have two replacement e-clips ready, the shaft was around 6mm to give you an idea of clip size and they were a pain to find locally at short notice!
Otherwise this is a straight swap, basically disconnect the hoses and fan (there is an access flap to get to the bottom hose on my Eunos), undo two bolts top left and right and lift out. Dead easy to do.
Reassemble, refill the radiator, run it with the expansion tank lid open a bit and heater on full blast. Job done.