I really like the Stealth Press by IconicFab, but the supplied mounts didn't fit the large barrel of the Hakko FX-600. Since IconicFab thoughtfully supplied the step files, I modified his largest design to accommodate it.
The FX-600 handle is tapered, and you want to grip it at the smaller location, but the hole has to be large enough to let the large section pass through. The mod works well for me, but you could always add some padding around the small section of the handle if you want a tighter fit.
The author remixed this model.
Modified mount to hold FX-600