Is this for a 12V system?
As a general rule of thumb, I like to de-rate the output of panels to 85% of nameplate. The current maximum is the OUTPUT current, which in this case is 60A. So, assuming you want to charge a 12V battery, and it starts bulk charging at ~13V, the math is... (60A X 13V)/85% = 917W.
Now the Volt limit of your controller is 160V. You have to remember to take cold weather voltage correction into account. At -40C, the correction factor is ~ 1.25X. That will get you close. For a really accurate voltage for your location's winter lows, use a string calculator like this one...
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But, using the quicky formula, expect the real-world Voc to not exceed 160V/1/25X = 128Voc. So, the max number of panels you could put in series is 5 at 145V. Six could reach 174Voc at -40C.
It turns out that 5 in series would be making you 900W, which is just under that limit of 917W. As an alternative, if you want a bit more power than this, you could implement 6 panels, but wire them in a 3S2P configuration. The two strings would need to be pointing in two different directions so the noon peak does not exceed 60A. A string facing southeast, and another facing southwest would accomplish this.