It may be possible with massive amounts of effort and custom fabrication. There have been some detailed discussions about rack & pinion conversions in early Celicas, do a search if you want the full story - but trust me you don't want to go through all of that just to get power steering.
Might I suggest you spend some time at the gym if you can't deal with manual steering in an RA23? I have 205 tyres on mine and I don't have any dramas even at parking speeds!
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