Ok, just pulled the clip off my Toad, tried it against a Kiwi, here's the deal.
Length is not really a problem, although the shorter clip from a Pegasus might work better (Toad clip is 2 1/4", Pegasus 2 1/8").
The major problems are width (which is more of a problem if its jigged bone than if it is a stainless) and the fact that the scales/bolsters of a Kiwi are not flat. So first you have to file or mill a flat on the bolster. Next problem, if it's a bone Kiwi, is that the lock pivot pin protrudes above the bone. You might be able to grind this down flush, if so then the clip could be installed without modification, otherwise, in order to clear the pin you would either have to thin the clip, or live with the fact that it was higher than the scale.
They say a picture is worth 1000 words so, maybe the attached will be more help than my ramblings.