Customizing Signature fields in Document using adobe sign API

I'm using adobe sign api's to send document for signatures, in current behaviour signature fields are being added to end of document. Can we customize the location and appearance of signature fields? and have found some relevent information from this link: https://helpx.adobe.com/sign/kb/place-form-fields-in-a-document-using-rest-api-adobe-sign.html but is seems like outdated implementation and not working currently. Any help? Thanks In Advance.

I have found two solution, there is two ways we can control form fields:

1. Using text tag that we should put in our document and adobe automatically convert it to signature filed

       Here is the link

2. Other way is using v6 api endpoint, the link mentioned in question is not for V6 api. Here is the link through which we can update form filed.

Out of above two approach, I found the first one best. It also provide lot of other flexibility.