I've been out of town all day. I just responded to the email. That cable is too small, not rigid enough, and routed backwards. You need a much thicker (new) cable long enough to connect to the lever from the other direction so pulling the knob engages the PTO. First, it's imperative to remove the box, free up the linkage, and use the proper stack of shims and gaskets between the PTO and the transmission case so the slide gear can engage the transmission cluster gear without having to force it. The spacing of the box from the case is a very critical dimension. Most PTO's have a plug or a bolt hole to allow a dial indicator to be used to check the backlash of the driven gear when it's engaged with the transmission. The lever should move easily when engaging the gear, but with a minimum of backlash. If the box is too close to the trans case, the gear teeth will bottom out. If it's too far away, there will be a lot of slack and rapid wear of the gears.
Jerry

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