add subheadings

Author: paigecalvert

docs/reference/custom-resource-helmchart-v2.mdx

@@ -89,22 +89,26 @@ For an example of recursive and non-recursive merging, see [About Recursive Merg
 
 ## builder
 
-The `builder` key contains the minimum Helm values required so that the output of `helm template` includes all container images needed to install and run the chart in an air-gapped environment.
+#### Overview
 
-The Replicated Vendor Portal uses the values in the `builder` key to run `helm template` on the chart, then parses the output to discover the list of images that the Helm chart requires. This list of required images is used to create the `.airgap` bundle for the release, and to build the Helm air gap installation instructions available in the Replicated Enterprise Portal.
+The `builder` key contains the minimum Helm values required so that the output of `helm template` exposes all container images needed to install the chart in an air-gapped environment.
 
-The `builder` key is required for the following use cases:
+The Replicated Vendor Portal uses the Helm values that you provide in the `builder` key to run `helm template` on the chart, then parses the output to discover the list of required images for the chart. This list of required images is used to create the `.airgap` bundle for the release (for air gap installations with a Replicated installer), and to create the Helm air gap installation instructions available to customers in the Replicated Enterprise Portal or Download Portal.
+
+The `builder` key is required to support the following installation types:
 
 * Air gap installations with a Replicated installer (Embedded Cluster, KOTS, kURL)
 * Air gap installations with Helm
-* Online installations with a Replicated installer where the user configured a local image registry
+* Online installations with a Replicated installer where the user configured a local image registry in the Admin Console
+
+#### Requirements
 
 <HelmBuilderRequirements/>
 
-**Example:**
+#### Example
 
 <BuilderExample/>
 
-For more information about building `.airgap` bundles for installations with a Replicated installer (Embedded Cluster, KOTS, kURL), see [Package Air Gap Bundles for Helm Charts](/vendor/helm-packaging-airgap-bundles).
+For more information about how to build `.airgap` bundles for installations with a Replicated installer (Embedded Cluster, KOTS, kURL), see [Package Air Gap Bundles for Helm Charts](/vendor/helm-packaging-airgap-bundles).
 
-For more information about installing with Helm in air-gapped environments, see [Install and Update with Helm in Air Gap Environments](/vendor/helm-install-airgap).
+For more information about how to install with Helm in air-gapped environments, see [Install and Update with Helm in Air Gap Environments](/vendor/helm-install-airgap).