I recently bought a Porter-Cable Heavy Duty Circular Saw (MOdel 347). It has a 6-1/2 x 12 " heavy steel base plate (kind of like a waffle). I want to bolt a plywood base to this as per Cunningham's recommendation in Building the Greenland Kayak, but there are no bolt holes on the base. Does anyone familiar with this saw have any recommendations about what size holes to drill and/or where to drill them?

Thanks.

Wes