Custom Field Toggle option for Request types

We were looking to setup a custom form and add custom fields to the form as well. We only want these fields on the custom request form but you have to add a custom fields to the request type as a whole which also puts the custom fields on the normal request form as well.

If there was a toggleable option when adding the custom field to the request type that lets you dictate the custom field to only show on the custom form would be a massive improvement to the system.