R’ Yair Hoffman wrote an article for 5tjt, from which I quote:
Below we find the nusach of a Shtar Mechila as formulated by Rav Moshe Shternbuch Shlita of the EIda HaChareidis in Yerushalayim. It should be signed as soon as possible. There is, of course, no deadline as to when the form is signed, and it is often done many years later.
THE CHOSSON
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THE KALLAH
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