And you only get the free hole with purchase of a $60+ acrylic box. I think you can order their "turbo kit" by itself to add to your existing overflow. It is kind of a hard sell, for a penductor, a bulkhead, and a threaded street ell 90.
And no, the penductor won't preform very well with a Mag 10 (9.5?). Here's an excel sheet and graph I threw together of a Mag 12 and several Iwaki's for an example a few weeks ago.
That graph is considering 0' of other head on the pump. The intersection of the penductor with the pump's curve would be the output if the penductor was connected directly to the pump.