Looks like your SN is 61,182...
As I have read, the numbers mean this:
Serial Number breakdown:
SNT = Serial Numbered Tractor
10 = Model 110 (if this number was 12, then the tractor would be a model 112)
3 = Tire Code (GT-3 tires = 23x8.5-12 high floatation rears/16x6.5-8 fronts
1 = Manual Lift (if this number was a 2, then the tractor would have hydraulic lift)
061182 = Actual Production Number
M = Made at the Horicon Factory