I wouldn't take polish to those. I've never worn Wellco's so I don't know from experience, but I've worn similar Bates and Bellvilles. The "leather" pieces are rough suede-esque, will just look a mess. I never did anything other than give them a healthy brushing. And while those vibram soles will stop a nail from going through your foot, I don't think they'll take color well. You'd be better off hunting down some of the old black boots they wore with the BDUs. There's some old salt with a pair or two of well polished ones out there. Check eBay.