Installing one wire alternator
Sorry for not mentioning the type of alternator its a 75 amp powermaster chrysler square back One wire internally regulated alternator.
OK. So the next questions are why? Usually people choose one of these for a particular reason or someone told them is was a good idea. If you are in the latter catagory, my recommendation is to exchange or return it.
Ratings: I've gone on about ratings games in other threads, but the key things are the following.
1. Power available at low rpm is significantly less than the rating, and higher rated alternators do not always produce more power at idle speeds. Sometimes less.
2. Actual power output depends on the demand, not the availability.
---Let me explain that.
To run a basic car with points or electronic ignition electric power is needed for the ignition and to power the alternator. That's around 4 amps at 14 Volts. (The power then is 4x14= 56 Watts). With the alternator regulated to produce power at 14 Volts, the alternator output will be 4 amps. The current flowing out will be 4 amps whether the alternator is capable of producing 4, 40, or 140 amps at idle.
Turning on the lights, stepping the brake (brake lights), turning on the wipers of course increase that demand. But the power needs are still pretty modest. Depending on the car options, year, the bulbs etc, 20 to 30 amps is really all that's needed to run things.
The one item I have not mentioned yet is that can draw a lot of current is a discharged battery. This is a variable load. As a battery recharges, it draws less and less current. Fully recharged, the battery draws no current.
Connecting direct to the battery:
If you connect this one wire alternator output direct to the battery, and no other changes, all of the power to run the car (except the alternator's field) will go to the battery first, then through multiple connections, through the ammeter and finally to the main splice. (assuming this isn't a '76 or other less typical wiring)
Each connection and the distances, especially in a hot engine bay, will all contribute to resistance to flow.
Besides the extra distance and connections there will be some other issues to be aware of.
1 The ammeter will show discharge all the time.
2 The original battery output wire (R6) and field power wire(s) need to be removed or otherwise made so they can not ever touch ground.
3 A short in the alternator wiring will cause the battery to discharge until the wiring burns up. The bigger the wire - the longer it will take to burn.