A question about change unit's feet size?

I can change a unit's size ... but how can I change a unit's feet size?
tell me thanks~:)

i dont know, but if u change collision size it makes foot prints bigger/smaller

To the best of my knowledge, you can only change a units size, not a specific part.

The only way would be to edit the model. Perhaps you could remove all the model but the feet, and attach those to a 2nd model w/out feet. Then again...why not just scale the feet once you have a model of them? Other than editing the model, however, you can't scale parts of a model.