My suggestion is to take a step back.
Lets start with the premise - a short to ground.
A serious short to ground in the turn signals or hazzard should cause the flasher unit to open like a circuit breaker. Hazzards were also always fused, turn signals were not. We'll have to look at the shop manual or operators booklet for '71 to know if they were fused that year.
A serious short to ground before the fusebox will cause the engine to stop running (if it was) and the fusible link to melt.
The fusible link is in the battery line - usually right at the bulkhead connector.
Even though the ammeter is labeled alternator it is not in the alternator line. Its in the battery line. It shows the flow of current into or out of the battery. If the battery is discharging when it should be charged, then the alternator is not supplying the power to the run car. In that sense its an alternator gage. A little confusing in terminaology. Just remember it shows Discharge and Charge.
Here's the basic layout.
View attachment 1716095238
Some details may be different. For example I think the hazzard flasher is on the same fuse as the brake light switch.
Go to
www.mymopar.com and download the service manual.
You may wish to buy a paper copy as well but the digital pdf will get you going.