Don't know anybody who rides a ski "Dry Weight"; Fuel adds about 30 lbs to the total weight.
My numbers were approximate (did you notice the +) to show the roughly 100 lb weight difference 'tween a SJ and an SXR which is what matters, but since you want to get precise...
SXR 800 Dry Weight = 352lbs plus a 4.5 gallon Tank = 27lbs, Total Weight = 379lbs
SJ 701 Dry Weight = 291lbs plus a 4.8 gallon Tank = 29lbs, Total Weight = 320lbs
Your SJ Dry Weight number is wrong for a 1994 SuperJet, which is what faceplant2 rides...