Customize a Signature Block

How would one go about adding to or editing fields in a signature block, so that it can be customized and then saved for use on later forms? The default signature block with a signature line and email is useful in some circumstances, and other times something different would be helpful.

I could always build it piece by piece every time using signature fields, butIwould like to be able to justbuild it once and load it as a block from an existing archive.