Well, if you don't want to use a deployment server then edit the /etc/system/local/inputs.conf then restart the forwarder.
After restart of the service.
Checking what Splunk thinks of the config files:
./splunk cmd btool list
./splunk cmd btool list --debug
The above command takes a config file parameter and shows you the ‘implied’ settings. With the –debug flag, it tells you which location it read them from.
./splunk cmd btool inputs list --debug
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