Hi wkeyser,
I have not done this but I know others have with few problems. They have just used the rules as written but adjusted the scale to fit, see below.
Yet you might want to just play it as it is and use your battalions as brigades. The rules are very flexible and the basic distance used is half of the frontage of a unit when in Line. For example Cavalry move 3 times this distance in line. All infantry and cavalry units should have the same frontage but that frontage can be whatever you like.
So you could use one of your battalions as a brigade/unit and then the distances would be multiples of half the frontage of one of your battalions. But also you could use 4 of your battalions as a brigade/unit and the distances would be multiples of the frontage of 2 of your battalions.
I would recommend thinking about the size of table you want to use. If you have a unit frontage of about 120mm then most historical battles can be fought on a table 1.8 meters long (6 feet). If you have a unit frontage of 240mm then you will need a 3.6m table!
As a guide the battle of Blenheim is about 40 infantry and cavalry units a side. If you have a unit frontage of 120mm then this is fought on a 2.4 meter table (8 feet) - Blenheim is one of the bigger battles.
So in short I don't think you will have any probems doing this but you might want to just use 1 or more of your battalions as a brigade and play that way.
I hope that helps.