Change the existing Sign customiser on template using app blocks

Find the neon customizer ID you would like to replace the existing neon customizer with.

•  In Shopify admin go to apps => Neon Product Customizer
• Click on Customizers in the top right corner
• Make note of the customizer ID in the list 

1. In your Shopify admin click  Themes, and then click Customizer next to the theme on which your existing customizer is currently installed, I am using the dawn theme for the demonstration:

2. Go to the existing template page that your customizer currently lives on.

• on the top bar, click on the dropdown that says Home page
• In the expanded list, either in products or pages, find the template that your customizer lives on and click on that template.

3. In the Shopify template editor left-hand sidebar, click on Neon Customizer

4. Using the customizer ID you found in step 1, update the value here 

5. In the Shopify template editor hit Save.

You are all done!