Hi Steve,
I presume, the holes at the buckle you have used at the limit to shorten it. How much links are on each side?

It is possible to open the rings with a smal knife / scew driver, but I would not thouch it further, because you will see this point of repair for ever, worst case will be, you break some rings or if you work near the clasp even break the connection part. This is difficult , not impossible, to recource, but expensive.

cheers
mich