Json\variant - delete member

Hi
Can anyone help with deleting members for either Json on Variant.

I am updating invoices , and get Json from the API via Httprequest.
I then do JsonToVariant and make the changes to some of the members and now need to pass the Json back to the API via VariantToJson and all shoul dbe good.

How ever I need to delete certain memebrs that I must NOT pass back to the api.

Whats the easiest way to do this .

EG: vMyJson.RowID = 1224 needs to be deleted

looking for a member delete option ?