Siege of Fort Niagra July 1779

I'm stretching history a bit. I'm going to have an action by General Sullivan contine from the Mohawk valley up to the fort.
Some British, mostly Mohawk and Canadien defenders
American units from the army

So I have begun to set up this battle. Main issue as my son noted is that the American force seems small to try and take on a British held fort. However, I will see about enlarging the American force, including potential Artillery.

Eventually the Crown forces were able to cut apart the Americans but not to the extent they thought they could. The Royal Artillery failed in their counter battery fire, and the Americans were close to taking the fort, however British musketry kept them at bay.