When I had my Novamill, I made a tooling plate from some flat bar, with a bit gauge steel dowelled along the rear edge, then used MiteeBite edge clamps to hold lengths of flat bar in place.

There's a photo at https://www.flickr.com/photos/mc_mtb...n/photostream/

IIRC it was made from either 1/2" or 15mm bar to give enough depth for recessing the mounting bolts