Some of the first steps are so obvious so I wont bother with them so I will start with the good stuff.      

You first take your radiator that you are going to use and put it in as if you were going to mount it and then you need to grind out a small notch (1/4") in each side of the front frame support (EXACTLY where your radiator seems stick out and touch the frame) so the radiator will fit forward just a small amount NOTE, it is very important that you mark the spots on the frame support with your radiator IN the car so you know that you are grinding in the right spot.

After the top frame is ground down, put the radiator back in the car and put the radiator in the very BACK of the rubber boots on the bottom. You will also need to find a way to hold the bottom of the radiator pushed forward in a very slight manor permanently.

put the electric fan down in there and move it around while pressing it up against the radiator (gently). At this point you are trying to determine the best place to mount the fan on the radiator. Once you have determined where the fan needs to be mounted you make marks on the radiator so you will know where to mount it when you get it on your bench.

I had to grind a small spot in the corner of the fan shroud for the radiator fastener to clear

Also notice that I kept the factory shroud support clips in bottom of the radiator and forced fit big washers in them. They are serving as extra vertical support for the radiator. Not that it is necessary but I would rather have it over supported than under supported. I used the same spacers/washers that you use with weld wheels.

You also need to mount an overflow reservoir on the fan shroud and those instructions are on the other fan install page on this site.

Here is a pic of the finished product and the clearance that I have.