Cannon downrigger base bolt patter

[djw13cwru]

Does anyone know what the bolt pattern is for the older square cannon downrigger bases with the lip at the top (i.e. the one used on Unitroll and magnum riggers)? Also, do you know what the bolt pattern is on the older style swivel base as well? I'm looking at upgrading some mounting plates, but the boat is still in storage so I can't take measurements. Thanks. 

[Sk8man]

If you are talking about  these  in the pics below the surface mounting holes are spaced 2 1/2 inches apart at the center of the holes while the outside base mounting holes on the swivel mount are spaced 4 inches apart on center. There is also another mounting base which I have on three of my riggers but unfortunately they are in the boat and not accessible at the moment but I think they are spaced the same.

Edited April 20, 2016 by Sk8man

[djw13cwru]

Thanks Sk8man, that is what I was looking for. The two bolt patterns on the swivel base cover both sets of bolt holes.

[Sk8man]

Yes good luck.