What concerns do I need to look into when running a high current alternator?

It's not clear to me whether the ammeter in your car has been eliminated or not. Please read this article on the subject:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

You need to modify the wiring if it has not been, and run the alternator output DIRECTLY to the battery with about a no 6 wire.

Pull all loads off the battery or starter relay stud, and make sure they are properly fused/ breaker protected as close to the battery as you can get.

Some of us have removed our ammeters and "converted" them to voltmeters. This will vary with your skill and the car, but in the case of my Dart, it was VERY easy, an afternoon project:

http://www.forabodiesonly.com/mopar/showthread.php?t=119480&highlight=ammeter+conversion

My Dart dash is like the one shown near the top of page 3 of that thread. A Sunpro voltmeter for 20 bucks, mounted in place of the ammeter, and the adjustment pot set so that 14V is centered on the original scale. I didn't even bother to glue the old needle on, just left the Sunpro needle as is.