Turns out I have the FSR manual, copied below in case it's helpful.
850 would probably be overkill for me but I might get back to you after the weekend.
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RockShox Deluxe -
FSR, Comp & Extreme:
Frame Size / Spring Rate / Rider Weight.
S / 650lbs / 130-160
M / 650lbs / 130-160
L / 750lbs / 150-180
XL / 850lbs / 180-210
FSR Elite:
S / 700lbs / 130-160
M / 700lbs / 130-160
L / 800lbs / 150-180
XL / 900lbs / 170-200
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