I'm trying to buy something for my fiance for his 4 wheeler for his birthday. Wanting to get him some Stick Stoppers but I have to know whether he has a 420 or 350. I know he has a Rancher ES 4x4, 2010(I think). Can anyone tell me how I can figure out which kind he has? I don't want to ask him and ruin the surprise if I can find out on my own. Thanks!