Figured I would put together a parts list for upgrading to a high amp alternator. I will link the parts from all from summit as a reference for what to look for.
http://www.summitracing.com/parts/pco-8096s/overview/ 6 Gauge wire 50ft. 8 Gauge is safe enough for a 100 amp, however if you go with a 140 amp system the 6 gauge still has you covered.
http://www.summitracing.com/parts/pco-4138kt/overview/ Some nice copper stud rings, can be had from 1/2 inch down to 1/4 inch. Recommend crimping and soldering these (keeps the corrosion down)
http://www.summitracing.com/parts/bss-cb185-110/overview/ Circuit breaker 110 Amp , can be had as high as 150 Amp. Get the next model higher in rated amperage from your alternator, so small spikes won't trip it. These two components can be used with one wire style, or the factory regulator.
http://www.summitracing.com/parts/tff-7509rfsp/overview/make/dodge Tuff Stuff 100 Amp Alternator. This one is the highest rated with a factory appearance that I was able to find.
They do have them listed as high as 200 Amps,
http://www.summitracing.com/parts/pwm-8-47539/overview/make/dodge but they will not have a factory apperance. How they will fit in a factory mount, I also have no idea. To go this high you will be looking at 4 gauge wire to be safe.
The wire gauge sizes I listed also assume a relatively short length. If you have a Trunk mounted battery you should check the length of the charge wire. If its too long you may exceed the recommended amperage for the wire at that particular length. This chart should help give you an idea
http://www.wattco.net/infopdf/wireguagechart.pdf . Most rating chart list wire amperage based on a constant loaded rating. Our cars charging systems don't charge at max for that long, that's why my 87 W-150 with the 100 amp factory option only has 8 Gauge wire.
A hundred amp system is enough to run a dual electric cooling fan set up, high powered ignition, new style A/C components, and still keep the battery happily charged. If you want a high powered stereo set up on top of that you'll need to go higher amperage system yet.