Just a thought but I have a vintage machine with a knee control , I love it . I do have my newer machine for some stuff , but I just love the knee control... wish they still made them. I spoke to my trusty repair man once about trying to convert my new machine to a knee control, he suggest first mounting the foot petal on a cabinet /table at the knee height , using wood blocks to get it to the right distance from the top and side. This might be a viable solution for you.