Has anyone tried replacing the standard "wet" power steering with an electric motor directly on the column - a la Vauxhall Corsa system?
I doubt it.
Some people delete the PAS completely.
You have to be careful with electric can ruin the feedback feel etc.
Funnily enough this is a popular conversion on a camper van forum I use and I think the Corsa system is popular on other makes which puts them in some demand.
Usually though they are used to convert from a non power steering situation so I'm not sure what has to happen with the existing Toyota rack. Presumably that has to be disabled in some way but ,as said, that has been done, usually for track / race.
If you want I can dig out the contact involved. I doubt that he has any experience whatsoever of the 2 but he may provide some good background on what will be involved.