If you recore the radiator, only the two brass tanks and the two steel straps will be reused. You can have the radiator shop install whatever nipple configuration that you desire.
If you buy a new radiator, any radiator shop can change or modify the nipples. You could even have short straight nipple(s) installed and use a 90° hose.
This would save you the additional expense of purchasing the Mirriahs.
If you do use the Mirriahs, the diameter of the motor housing is slightly larger than the stock fan motors, which will require you to massage the retaining straps and use a longer screw on the top.
You will need to pay attention to the location of the fan blade relative to the radiator AND to the shroud above the fans.
Check for proper rotation of the fans. With the fans running, hold a piece of paper behind the radiator; the paper should NOT be sucked into the radiator. Check both fans.
With the Mirriah fans installed, you may experience engine "run on". If this happens, DO NOT use a diode in the fan's wiring. If need be, I can advise you of a solution.