The Spriso Motorsports Subaru Justy alternator bracket was originally designed for a Datsun Roadster application where the stock SR20 water neck would not work due to the narrow frame rails in the engine compartment and the wide variety of radiator packages that people use with their conversions.
Over the years, our setup has been very popular with people wanting a low-profile alternator conversion for the SR engine in truck or other chassis as well. For many people, modifying the water neck to suit their individual application makes for a cleaner conversion, and more straightforward hose routing to the lower radiator neck. If this is too difficult, or you don't have the means to make such a modification, then perhaps the other bracket listed above might be a better solution for your application.
As with anything, your mileage may vary...
Spriso