Now, you need to "enable" the plugin.
Open the file ".../player/CustomPluginVariables.JSON" and change the line :
"StockCarRules.dll":{" Enabled":1,
That should be it.
Open the file ".../player/CustomPluginVariables.JSON" and change the line :
"StockCarRules.dll":{" Enabled":1,
That should be it.