To a first approximation figure 33 amps, not 66, even though two of the three AC lines are connected. You're using one phase out of three.
(You can actually go a bit higher because for part of the cycle the currents add in 3 phase and you don't have the added current in single-phase so you can use the full current for one phase rather than splitting it between two. I don't recall the ratio of the top of my head and I'm busy right now. Maybe somebody else will tell you.)
I would now IMMEDIATELY throw out the selenium rectifier and vent the shop until you don't smell it any more. That stuff is REALLY BAD for you. Stop exposing yourself and your family NOW. (At this point you should survive but your breath and sweat may smell like garlic for years.)