Digital signatures aren't "over" anything. They belong to the document as a whole, and can be inspected in the Signatures tab.
You can have an appearance for the signature, but these are without value. I think that appearances should be banned, because they fool people into trusting what is on the page, which is the exact opposite of the idea of digital signatures.
I am a bit confused as to what you already have and what you need to create.
So, you already have a button field in your PDF (which you call "clickable stamp") and you want to place digital signature appearance (which is an annotation) at the same place on the page where the button field is (over the "stamp"), and retain ability to click on the button. Is this correct? Do you also have an unsigned signature field in the same location, or do you just drwa a rectangle and sign in it?
Or you have nothing and want to design a document that behaves in the way you descibed from scratch. If this is the case then you need to learn Acrobat, its forms handling tools and signature tools. This is a task not suited to be described on a forum page.
Thanks so much for the reply.
I don't have anything except a pic of the stamp which I can move to where needed on the clients pig drawing sent to me. Have another engineers work which shows a digital signature placed on the stamp. Click the signature or area of stamp - I'm not sure & the report appears in same area as stamp with the time ( automatic) with info needed.
As you say, I may have to learn Acrobat.
Thanks for the time
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