Customizing factory-bot's scaffolding generator

When generating a new agenda like rails g scaffold HighScore game:string score:integer the factory_bot generators create file spec/factories/high_scores.rb.

  ...
  invoke      factory_bot
  create        spec/factories/high_scores.rb
  ...

I Want to customize, that generator, so I write my own one. But I don't know where to save my new template, so the scaffold generator can use it.

I tried:

lib/templates/rspec/factory_bot.rb
lib/templates/rspec/scaffold/factory_bot.rb

Or my own generator:

lib/generators/rails/factory_bot_changes
lib/generators/rails/factory_bot_changes/USAGE
lib/generators/rails/factory_bot_changes/factory_bot_changes_generator.rb
lib/generators/rails/factory_bot_changes/templates
lib/generators/rails/factory_bot_changes/templates/factory_bot.rb

I also tried to change the config/application.rb

config.generators do |gen|
  gen.orm :active_record
  gen.template_engine :haml
  gen.test_framework :rspec,
                     fixtures: true,
                     view_specs: true,
                     helper_specs: true,
                     routing_specs: true,
                     controller_specs: true,
                     request_specs: true
  gen.helper :helper_and_policy
  gen.scaffold_controller :controller_with_smart_listing
  gen.fixture_replacement :factory_bot, dir: "spec/factories"
  # gen.fixture_replacement :factory_bot_changes, dir: "spec/factories"
  gen.factory_bot false
end

But nothing seems to be working.

Where should I save the new template, or how can I trigger my own generator after scaffolding is done, to replace the file?