Power Steering Pump differences

I think the article has a mistake in that brackets for the TRW and Federal pump vary. There are no brackets to fit a TRW pump to the later aluminum water pump (Ron Grubb's LA360). I had to change to a Federal pump after putting the aluminum water pump on my 1965 273. The Federal pump then sits much lower and barely cleared the K-frame. I also had to do tricks with belts and pulleys since the alum w.p. sticks out 1" farther. Don't be like me, so use the earlier iron water pump, but that also changes where your lower radiator outlet must be (driver's side). You will appreciate the extra 1" clearance to the radiator, which might allow fitting a clutch-fan.