You know, 60 amps isn't that much? Run 2oz copper on both sides of the board so you effectively end up w/ 4 oz; if you can accept a 25 deg C rise, that ends up at a 12mm wide track. Scale it up a bit - I don't know how space-constrained your application is - and you should be good to go.
(As a point of reference, consider high-end video cards with GPUs eating 150-200A. They're simple (well, "simple") multi-layer boards with no extra fuss.)