Rusty Cast Iron Sewing Maching Legs

I recently picked up this pair of Singer treadle sewing machine legs at an estate sale.  I got them cheap because they are heavily rusted.  Since I only have the legs, I'm planning on building a table with a shelf and small wine rack underneth it from some reclaimed wood I have.  But first, I need to deal with the rust.  My plan is to use a wire brush on a drill to remove as much of it as possible, then use Rust Reformer before painting them.  I've done this in the past to refinish sewing machine bases with good results (the first picture is a treadel base I refinished a while back), but I've never had any sewing machine legs quite this rusty.  I would appreciate any tips or suggestions on dealing with the heavy rust.