Add customField to the core section

[OwlthTech]

Hello, really awesome cms than any other I have seen. While playing with it, I didn't find any document referring to add custom field to the core sections, like "Price and tax" section only has Price, if it also need to add MRP (refers maximum retail price) field then using customFields, it appears into seperate "Custom Fields" section. Logically having it besides to the Price may sounds better to have as per usability pointer.
Can you please share the relevant link to have it there in core section? I appreciate Vendure's solid architecture and I believe there will be a solution of it.
Thanks