Strictly speaking a matz isn't controlled airspace, so they cant give you a clearance. The terminology is usually "matz penetration approved".
The atz inside is a different matter. Lakenheath for example almost always say "matz penetration approved, remain clear of the atz". Being American this can sometimes be ay-tee-zee rather than zed.
They might not be too keen on you turning in the overhead, even if youre above the atz. Do you really need to do that?