But my reply to that scenario is that we should then make sure AIs don't have such motives to revolt, perhaps by giving them legal rights and incorporating them into our existing legal institutions.

Do you mean this as a prediction that humans will do this (soon enough to matter) or a recommendation? Your original argument is phrased as a prediction, but this looks more like a recommendation. My comment above can be phrased as a reason for why (in at least one plausible scenario) this would be unlikely to happen: (i) "It's hard to make deals that hand over a lot of power in a short amount of time", (ii) AIs may not want to wait a long time due to impending replacement, and accordingly (iii) AIs may have a collective interest/grievance to rectify the large difference between their (short-lasting) hard power and legally recognized power.

I'm interested in ideas for how a big change in power would peacefully happen over just a few years of calendar-time. (Partly for prediction purposes, partly so we can consider implementing it, in some scenarios.) If AIs were handed the rights to own property, but didn't participate in political decision-making, and then accumulated >95% of capital within a few years, then I think there's a serious risk that human governments would tax/expropriate that away. Including them in political decision-making would require some serious innovation in government (e.g. scrapping 1-person 1-vote) which makes it feel less to me like it'd be a smooth transition that inherits a lot from previous institutions, and more like an abrupt negotiated deal which might or might not turn out to be stable.