The showdown over how long to extend Madison Square Garden’s “special permit” to stay at its home of over a half-century is scheduled at the OK Corral — aka the City Council’s Subcommittee on Zoning and Franchises — Monday.

Spectators at the 1 p.m. session on the 14th floor of 250 Broadway might want to duck.

The Dolan family, which owns the Garden, wants the license to be immortal.

The City Planning Commission recommends a 10-year extension that would require the Dolans to upgrade surrounding streets and sidewalks and work with transit agencies to make improvements to Penn Station.

But “Move the Garden” advocates insist the Council limit a permit renewal to three years.

Many state elected officials, Community Board Five members, architects, and urban-planning and civic organizations insist that the only way to create a truly better station is by taking MSG off the top of it.

The committee vote will need to be seconded by the full Council later.

But whatever the outcome, expect howling from whichever faction doesn’t get what it wants.